Healthcare centres serving tens of thousands of refugees on the Thai-Myanmar border have been ordered shut after US President Donald Trump froze most foreign aid last week, forcing Thai officials to transport the sickest patients to other facilities.

The International Rescue Committee (IRC), which funds the clinics with US support, told the facilities to shut by Friday, January 31, according to a local official and two camp committee members.

The IRC did not respond to a request for comment.

Trump last week paused development assistance from the US Agency for International Development for 90 days to assess compatibility with his “America First” policy.

The freeze has thrown the global aid sector, which is heavily funded by the US, into chaos.

It was not immediately clear what impact a waiver for life-saving humanitarian assistance during the 90-day pause issued by the State Department on Tuesday would have, or how many centres across the nine camps housing some 100,000 people were impacted.

The health facilities on the border serve tens of thousands of refugees from conflict-torn Myanmar.

Bweh Say, a member of the refugee committee at Mae La camp, in Tha Song Yang district, and a local schoolteacher said on Wednesday the IRC had already discharged patients and stopped people including pregnant women and people with breathing difficulties dependent on oxygen tanks from using their equipment and medicine.

The camp’s water distribution and garbage disposal systems, which the organisation had also been helping with, were also affected, they said.

Relatives of some of those discharged were “trying to find oxygen tanks” to bring home, Bweh Say said.

About 50 patients had been discharged, while several severely ill patients remained in the Mae La hospital, including a child recovering from heart surgery, said the schoolteacher, declining to be named because they were not authorised to speak publicly.

“Normally that hospital receives about 100 out-patients per day and now none,” the teacher said.

Chucheep Pongchai, governor of Tak province, told Thai media that the most severely ill patients would be transferred to local state hospitals, adding that officials have asked the IRC for use of their equipment.

Dr Tawatchai Yingtaweesak, Director of Tha Song Yang hospital, said he was travelling to the camp to assess patients.

“We have to assess which patients can go home, which patients need help with oxygen and so on,” he told Reuters by phone.

Nai Aue Mon, the programme director of the Human Rights Foundation of Monland (HURFOM), a grassroots organisation in southern Myanmar, said there was growing concern that basic healthcare needs in the camps would go unmet.

“It’s scary because these refugees depend entirely on this assistance for their day-to-day health services.”