Field hospitals in Thai refugee camps, landmine clearance in war zones, and drugs to treat millions suffering from diseases such as HIV are among the programs facing the chop as President Donald Trump contemplates massive cuts to U.S. foreign aid.Trump last week paused development assistance from the U.S. Agency for International Development for 90 days to assess compatibility with his "America First" policy, setting alarm bells ringing among aid groups around the world that depend on U.S. largesse.Humanitarian organisations and U.N. agencies say they could face drastic curbs on their ability to distribute food, shelter and healthcare if the freeze becomes permanent.The U.S. is by far the biggest contributor to global humanitarian aid, supplying an estimated $13.9 billion in 2024, accounting for 42% of all aid tracked by the United Nations.Clinics at camps in Thailand providing shelter for about 100,000 refugees from Myanmar were ordered to shut after the U.S. froze funding to the International Rescue Committee, according to a senior aid worker.Washington said it would grant waivers to the freeze in some areas including emergency food assistance, according to a memo seen by Reuters. Bangladesh's government said in a statement that the U.S. had granted a waiver for emergency food aid to more than a million Rohingya refugees sheltering in Bangladesh.But the exemption does not apply to other humanitarian programming. A Bangladesh-based aid worker said organisations working on shelter, for example, would not be able to buy new materials for building and fixing homes for refugees.The cuts will also affect the supply of lifesaving drugs for HIV, malaria and tuberculosis around the globe, which millions of people depend on, according to another memo seen by Reuters.On Tuesday, contractors and partners who work with USAID began receiving such memos to stop work immediately.