WASHINGTON — Former Presidents Barack Obama and George W. Bush delivered rare open criticism of the Trump administration — and singer Bono recited a poem — in an emotional video farewell Monday with staffers of the U.S. Agency for International Development. Obama called the Trump administration’s dismantling of USAID “a colossal mistake.”

Monday was the last day as an independent agency for the six-decade-old humanitarian and development organization, created by President John F. Kennedy as a peaceful way of promoting U.S. national security by boosting goodwill and prosperity abroad.

Secretary of State Marco Rubio has ordered USAID absorbed into the State Department on Tuesday.

The former presidents and Bono spoke with thousands in the USAID community in a videoconference, which was billed as a closed-press event to allow political leaders and others privacy for sometimes angry and often teary remarks. Parts of the video were shared with The Associated Press.

They expressed their appreciation for the thousands of USAID staffers who have lost their jobs and life’s work. Their agency was one of the first and most fiercely targeted for government-cutting by President Donald Trump and his billionaire ally Elon Musk, with staffers abruptly locked out of systems and offices and terminated by mass emailing.

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 criticizing the monumental changes that Trump has made to U.S. programs.

Bush, who also spoke in a recorded message, went straight to the cuts in a landmark AIDS and HIV program started by his administration and credited with saving 25 million lives around the world.

“You’ve showed 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.