The administration notified USAID workers in emails and a notice posted online, the latest in a steady dismantling of the aid agency by returning political appointees from President Donald Trump’s first term and billionaire Elon Musk’s government-efficiency teams who call much of the spending on programs overseas wasteful.

The order takes effect just before midnight Friday and gives direct hires of the agency overseas — many of whom have been frantically packing up households in expectation of layoffs — 30 days to return home unless they are deemed essential. Contractors not determined to be essential also would be fired, the notice said.

The move had been rumored for several days and was the most extreme of several proposals considered for consolidating the agency into the State Department. Other options had included closures of smaller USAID missions and partial closures of larger ones.

Thousands of USAID employees already had been laid off and programs worldwide shut down after Trump imposed a sweeping freeze on foreign assistance. Despite outcry from Democratic lawmakers, the aid agency has been a special target as the new administration and Musk’s budget-slashing Department of Government Efficiency look to shrink the federal government.

They have ordered a spending stop that has paralyzed U.S.-funded aid and development work around the world, gutted the senior leadership and workforce with furloughs and firings, and closed Washington headquarters to staffers Monday. Lawmakers said the agency’s computer servers were carted away.

“Spent the weekend feeding USAID into the wood chipper,” Musk boasted on X.

The mass removal of thousands of staffers overseas and in Washington would doom billions of dollars in projects in some 120 countries, including security assistance to partners such as Ukraine as well as development work for clean water, job training and education, including for schoolgirls under Taliban rule in Afghanistan.

The U.S. is the world’s largest humanitarian donor by far. It spends less than 1% of its budget on foreign assistance, a smaller share of its budget than some countries.

Health programs like those credited with helping end polio and smallpox epidemics and an acclaimed HIV/AIDS program that saved more than 20 million lives in Africa already have stopped. So have monitoring and deployments of rapid-response teams for contagious diseases such as an Ebola outbreak in Uganda.

Hundreds of millions of dollars of food and medication already delivered by U.S. companies are sitting in ports because of the administration’s sudden shutdown of the agency.

Democratic lawmakers and others say the USAID is enshrined in legislation as an independent agency, and cannot be shut down without congressional approval. Supporters of USAID from both political parties say its work overseas is essential to countering the influence of Russia, China and other adversaries and rivals abroad, and to cementing alliances and partnerships.

The decision to withdraw direct-hire staff and their families earlier than their planned departures will likely cost the government tens of millions of dollars in travel and relocation costs.

Staff being placed on leave include both foreign and civil service officers who have legal protection against arbitrary dismissal and being placed on leave without reason.

The American Foreign Service Association, the union which represents U.S. diplomats, sent a notice to its members denouncing the decision and saying it was preparing legal action to counter or halt it.

Locally employed USAID staff, however, do not have much recourse and were excluded from the federal government’s voluntary buyout offer.

USAID staffers and families faced wrenching decisions as the rumors layoffs loomed, including whether to pull children out of school midyear. Some gave away pet cats and dogs, fearing the Trump administration would not give them time to complete the paperwork to bring the animals with them.

Tuesday’s notice said it would consider case-by-case exceptions for those needing more time. But with most of the agency’s staff soon off the job, it was unclear who would process such claims or other paperwork needed for the mass removal of thousands of overseas staffers.

Musk’s teams had taken USAID’s website offline over the weekend and it came back online Tuesday night, with the notice of recall or termination for global staffers its sole post.

The announcement came as Secretary of State Marco Rubio was on a five-nation tour of Central America and met with embassy and USAID staff at two of the region’s largest USAID missions: El Salvador and Guatemala on Monday and Tuesday.

Journalists accompanying Rubio were not allowed to witness the so-called “meet and greet” sessions in those two countries, but had been allowed in for a similar event in Panama on Sunday in which Rubio praised employees, particularly locals, for their dedication and service.

At a news conference earlier Tuesday, Rubio said he has “long supported foreign aid. I continue to support foreign aid. But foreign aid is not charity.” He noted that every dollar the U.S. spends must advance its national interests.

The online notice says those who will be exempted from leave include staffers responsible for “mission-critical functions, core leadership and specially designated programs” and would be informed by Thursday afternoon.

“Thank you for your service,” the notice concluded.