Former Presidents Barack Obama and George W. Bush have delivered rare open criticism of the Trump administration — and singer Bono held back tears as he recited a poem — in an emotional video farewell with staffers of the US Agency for International Development.
Monday was the last day as an independent agency for the six-decade-old humanitarian and development organisation, created by President John F. Kennedy as a peaceful way of promoting US national security by boosting goodwill and prosperity abroad.
Secretary of State Marco Rubio has ordered USAID to be absorbed into the State Department on Tuesday.
Trump claimed the agency was run by "radical left lunatics" and rife with "tremendous fraud." Musk called it "a criminal organisation."
Obama, speaking in a recorded statement, offered assurances to the aid and development workers, some listening from overseas.
"Your work has mattered and will matter for generations to come," he told them.
Obama has largely kept a low public profile during Trump's second term and refrained from criticising the monumental changes that Trump has made to US programmes and priorities at home and abroad.
"Gutting USAID is a travesty, and it's a tragedy. Because it's some of the most important work happening anywhere in the world," Obama said. He credited USAID with not only saving lives, but being a main factor in global economic growth that has turned some aid-receiving countries into US markets and trade partners.
The former Democratic president called Trump's dismantling of USAID a "colossal mistake" that hurts the US and predicted that "sooner or later, leaders on both sides of the aisle will realise how much you are needed."
Asked for comment, the State Department said it would be introducing the department's foreign assistance successor to USAID, to be called America First, this week.
"The new process will ensure there is proper oversight and that every tax dollar spent will help advance our national interests," the department said.

'Great strength of America'
Bush, who also spoke in a recorded message, went straight to the cuts in a landmark AIDS and HIV program started by his Republican administration and credited with saving 25 million lives around the world.
Bipartisan blowback from Congress to cutting the popular President's Emergency Plan for AIDS Relief, known as PEPFAR, helped save significant funding for the program. But cuts and rule changes have reduced the number getting the life-saving care.
"You've shown the great strength of America through your work — and that is your good heart," Bush told USAID staffers. "Is it in our national interests that 25 million people who would have died now live? I think it is, and so do you," he said.
Former Liberian President Ellen Johnson-Sirleaf, former Colombian President Juan Manual Santos and former US Ambassador to the UN Linda Thomas-Greenfield also spoke to the staffers.

14 million additional deaths
The comments from the two former presidents came as a new study published in The Lancet medical journal revealed that the cuts could result in over 14 million additional deaths by 2030.
The study estimated that over the past two decades, USAID-funded programmes have prevented more than 91 million deaths globally, including 30 million deaths among children.
Projections suggest that ongoing deep funding cuts - combined with the potential dismantling of the agency - could result in more than 14 million additional deaths by 2030, including 4.5 million deaths among children younger than 5 years, the study in The Lancet said.
Washington is the world's largest humanitarian aid donor, amounting to at least 38 percent of all contributions recorded by the United Nations. It disbursed $61 billion in foreign assistance last year, just over half of it via USAID, according to government data.
"Our estimates show that, unless the abrupt funding cuts announced and implemented in the first half of 2025 are reversed, a staggering number of avoidable deaths could occur by 2030," the study said.