The United States Agency for International Development (USAID) officially shut down on Tuesday, which was criticized by former U.S. Presidents Barack Obama and George W. Bush.

Meanwhile, the USAID will be merged into the U.S. State Department from Tuesday.

According to an earlier statement of the U.S. State Department, the reorganization of the USAID involves realigning certain USAID functions with the State Department by Tuesday. Other USAID functions, which do not align with incumbent President Donald Trump's policy priorities, will be terminated.

In separate statements, Obama called the Trump administration's dismantling of USAID "a colossal mistake," while Bush quoted an AIDS relief program, whose future remains unclear, like much of U.S. foreign aid, as an example.

Trump had previously slammed the USAID as being run by "a bunch of radical lunatics."