Honduras’s president threatened to push the U.S. military out of a base it built decades ago in the Central American country should President-elect Donald J. Trump carry out mass deportations of undocumented immigrants from the United States.

The response by President Xiomara Castro of Honduras, in an address broadcast on television and radio on Wednesday, was the first concrete pushback by a leader in the region to Mr. Trump’s plan to send back millions of Latin American citizens living in the United States.

The threat came as Ms. Castro and Mexico’s president, Claudia Sheinbaum, also called a meeting of foreign ministers later this month to address the deportation issue.

“Faced with a hostile attitude of mass expulsion of our brothers, we would have to consider a change in our policies of cooperation with the United States, especially in the military arena,” Ms. Castro said.

“Without paying a cent for decades,” she added, “they maintain military bases in our territory, which in this case would lose all reason to exist in Honduras.”

Honduras’ foreign minister, Enrique Reina, said afterward in a radio interview that Honduras’s leader had the power to suspend without the approval of the country’s Congress a decades-old agreement with the United States that allowed it to build the Soto Cano air base and operate America’s largest military task force in Central America from there.

A spokesman for the Trump transition team, Brian Hughes, responded to Ms. Castro’s warning, saying in a statement, “The Trump administration looks forward to engaging our Latin American partners to ensure our southern border is secure and illegal immigrants can be returned to their country of origin.”

Mr. Trump promised to swiftly deport undocumented immigrants when he took office, but his transition team has not shared any concrete plans, leaving Latin American governments guessing even as they try to prepare. Mr. Trump also vowed to slap a 25 percent tariff on Mexico and Canada if they did not stop the flow of migrants and fentanyl to the United States.

Most governments in Latin America, including Mexico’s, have worked to stay on a good footing with Mr. Trump, even as they have sought to emphasize the contributions their citizens make to the American economy, whatever their legal status.

This week, Ms. Sheinbaum reiterated: “We will continue to demonstrate how the Mexican people in the U.S. contribute in a very important way to the U.S. economy. And if Mexican people were not in the U.S., there would be no food on American tables.”

The governments have also sought to reassure their citizens in the United States that they are preparing for any large-scale expulsions. Honduras has said it will establish mobile consulates, and Mexico created an online application for its citizens to alert consulate authorities if they are at imminent risk of being detained.

On Friday, Ms. Sheinbaum also suggested that Mexico might take in deportees from other countries — an apparent shift from her previous goal to reach a deal with Mr. Trump to avoid receiving such migrants — even as she reiterated that her administration did not agree with mass deportations.

“We are going to ask the United States that, as far as possible, migrants who are not from Mexico can be taken to their countries of origin. And if not, we can collaborate through different mechanisms,” Ms. Sheinbaum said.

“There will be a time to talk with the U.S. government if these deportations really occur,” she added. “But here we are going to receive them; we are going to receive them well, and we have a plan.”

Governments in the region rely on remittances from immigrants in the United States. They account for as much as 25 percent of Honduras’s economy. More than half a million undocumented Hondurans — about 5 percent of the Honduran population — were estimated to be living in the United States in 2022, according to the Pew Research Center.

Since the 1980s, an American task force has operated out of Soto Cano, an air base owned by the Honduran government in Comayagua, a town about 50 miles from the capital, Tegucigalpa. It was originally built by the United States in the 1980s to help contain the communist threat in the region.

Soto Cano currently hosts more than a thousand American military and civilian personnel, a spokeswoman for the task force there, Joint Task Force Bravo, said on Friday.

“We are guests of the Honduran government on a Honduran base,” said the spokeswoman, Capt. Hillary Gibson.

While the task force has played a role in counternarcotics efforts, Captain Gibson said, it has recently focused on disaster relief and administering humanitarian aid.

The United States Embassy in Honduras did not immediately respond to a request for comment.

The U.S. military maintains a presence at bases in other countries in the region, including in El Salvador, though these have fewer U.S. military troops than Soto Cano.

While many Hondurans celebrated Ms. Castro’s statements, some elected officials sought to distance themselves from the president. Several members of Congress noted the need for dialogue with the Trump administration and pointed out that pushing out the U.S. military from the base would not stop Mr. Trump from carrying out mass deportations.

Mr. Reina, the foreign minister, said on Thursday that Honduras intended to stay on good terms with the United States. But he stood behind the president’s statements, saying that “if mass deportations that violate the rights of migrants come about,” the country’s leaders had “a right to rethink” its relationship with the United States.

Will Freeman, a fellow in Latin America studies at the Council on Foreign Relations in New York, said of the Honduran president’s statement: “I’m surprised a bit by the boldness of it.”

He noted that while Ms. Castro had recently taken what he described as a publicly confrontational approach to the United States — including moving to end a longstanding extradition treaty — the country remained its largest trading partner. And Ms. Castro had been known behind closed doors to “play friendly” with the U.S. ambassador, he said, trying to elicit America’s continued support, including for humanitarian assistance around the migration crisis.

Mr. Freeman said it was also surprising that Ms. Castro would take this position before Mr. Trump assumed office, particularly in light of statements from Mr. Trump’s pick for secretary of state, Marco Rubio, the Republican senator from Florida.

Mr. Rubio had warned that Honduras under Ms. Castro’s government could become “the next Venezuela,” Mr. Freeman said, where a spiraling crisis under the authoritarian rule of Nicolás Maduro has led to mass migration.

“I think it will sour the relationship, which would have already been sour, with the Trump administration,” Mr. Freeman said. “And I don’t see these northern Central American countries are in a position to leverage much with the U.S. over the shape of migration policy.”

“Now Mexico,” he added, “is a totally different story.”

The United States does not have full diplomatic relations with some countries in the region, including Venezuela and Cuba, which have faced harsh U.S. sanctions. As a result, these countries are unlikely to accept large numbers of deportation flights.

After Ms. Castro’s address, Honduras’s foreign minister announced on social media the meeting between foreign ministers to discuss mass deportations, which he said had been called by the leaders of Honduras and Mexico. The post was accompanied by a photo of Ms. Castro holding hands with Ms. Sheinbaum.

Emiliano Rodríguez Mega contributed reporting.

The Treasury Department imposed sanctions on a Beijing-based cybersecurity company on Friday, blaming it for helping Chinese hackers infiltrate U.S. communications systems and conduct surveillance across four continents.

In an announcement, the department said the company, Integrity Technology Group, had supported a Chinese state-sponsored hacking group known as Flax Typhoon in a campaign to break into foreign networks between the summer of 2022 and 2023, saying it found the group had “routinely sent and received information from Integrity Tech infrastructure.”

The action came after the Treasury Department revealed in a letter to lawmakers this week that a Chinese intelligence agency had breached its systems in what appeared to be an espionage operation, gaining access to the workstations of government employees and unclassified documents.

A spokesman for the department did not specify whether Flax Typhoon had been implicated in the attack on the Treasury Department’s systems, or whether the sanctions were merely part of a larger operation to disrupt China’s cybercapabilities.

The sanctions also follow the much more damaging revelation last year that a group linked to Chinese intelligence agencies and known as Salt Typhoon had hacked U.S. telecommunications networks, targeting the telephone conversations and text messages of an array of top political figures, including President-elect Donald J. Trump.

Like Salt Typhoon, Flax Typhoon is among a handful of groups that Microsoft has publicly identified as being linked to Chinese intelligence and responsible for a range of state-sponsored cyberattacks. The group has been active since 2021 and appears focused on targets in Taiwan and the United States, according to the Congressional Research Service.

“The Treasury Department will not hesitate to hold malicious cyberactors and their enablers accountable for their actions,” Bradley T. Smith, an acting under secretary of the Treasury, said in a statement. “The United States will use all available tools to disrupt these threats as we continue working collaboratively to harden public and private sector cyberdefenses.”

In September, the F.B.I. said it had taken down a network of 200,000 consumer devices in the United States and abroad that had been compromised with malware and weaponized by Flax Typhoon.

The sanctions announced on Friday generally prohibit financial institutions and individuals from transacting with Integrity Technology Group, and freeze any of its assets in the United States.

It was not immediately clear what the breach of the Treasury Department may have achieved, but the agency represents an attractive target for state-sponsored hackers because of its Office of Foreign Assets Control, which is responsible for imposing sanctions and determining which individuals represent a threat to national security.

Should the United States follow the surgeon general’s call on Friday for cancer warning labels on alcohol, it would join a tiny contingent of nations that advise drinkers of the risk.

The World Health Organization concluded in 1988 that alcohol is carcinogenic to humans, and it has for years said that the harms of alcohol were well documented. “No safe amount of alcohol consumption for cancers can be established,” the W.H.O. reported in 2023.

But a group of researchers noted in a study published in 2020 that only a quarter of the world’s countries require any health warnings on alcohol. Their language is generally vague, and cancer warnings are rare.

The report from the U.S. surgeon general, Dr. Vivek Murthy, included an overview of studies and reviews published over the last 20 years, including a global study of 195 countries and territories involving 28 million people. The research found that greater alcohol consumption was associated with higher risks of cancer.

Here are a few countries that have linked cancer to alcohol or are considering more aggressive labels.

South Korea

Only South Korea has a label warning about liver cancer. In 2016, the country mandated a group of labels for alcohol, some of which include warnings about liver cancer.

Manufacturers can choose, however, to apply alternative labels that don’t mention cancer on their products.

South Korea has long ranked high among countries for alcohol consumption, according to the W.H.O. The authorities in the country have sometimes tried to take action against the national drinking culture. In 2012, for instance, the police in Seoul announced a crackdown on drunken violence.

Ireland

Beginning in 2026, labels that read “THERE IS A DIRECT LINK BETWEEN ALCOHOL AND FATAL CANCERS” and “DRINKING ALCOHOL CAUSES LIVER DISEASE” in red capital letters will be required on all containers of beer, wine and liquor sold in Ireland.

The rule was signed into law in 2023 and would make Ireland the first nation to mandate the public linking of any level of drinking to cancer, according to the World Cancer Research Fund.

Ireland has for years sought different aggressive measures to curb the use of alcohol. In 2022, the country imposed a minimum price on alcohol, a move that the nation’s public health minister, Stephen Donnelly, called “designed to reduce serious illness and death from alcohol consumption and to reduce the pressure on our health services from alcohol-related conditions.”

Ireland has been on the forefront of other public health policies in the past. In 2004, it became the first country to ban smoking in indoor workplaces, including bars and restaurants. Since implementation, more than 70 countries have followed suit.

Other countries’ efforts

Norway already greatly regulates alcohol, restricting beer sales to before 8 p.m. on weekdays and 6 p.m. on Saturdays, and selling wine, spirits and “strong beer” only in state alcohol shops. But in recent years the country has been developing proposals to include cancer warnings, according to local news media.

Thailand is also working on regulation that would require alcohol to have labels with graphic images and text warnings such as “alcoholic beverages can cause cancer,” according to The Bangkok Post. Industry groups have criticized the proposal.

Although Canada does not mandate cancer warnings on alcohol, a bill that would require labels that note a direct link was introduced in the Canadian Parliament in 2022. A group of researchers in Canada sought to study the effect of warning labels mentioning cancer in 2017, but the complaints by alcohol trade groups led a local government to pause the study.

In recent years, the authorities in Canada, Britain and several other countries have endorsed the idea that there’s no safe level of drinking. Some governments of countries with high rates of drinking have also moved to reduce consumption, including in Russia, where the effort has been one of its main public health goals.

Roni Caryn Rabin and Ted Alcorn contributed reporting.