The first U.S. military aircraft carrying detained migrants to Guantanamo Bay is expected to depart on Tuesday, U.S. officials said, as President Donald Trump's administration prepares to potentially house tens of thousands of migrants at the naval base in Cuba.

The first military flights to deport migrants from the United States to Naval Base Guantanamo Bay were slated to take off Tuesday.

A U.S. official says the first U.S. military flight to deport migrants from the United States to Guantanamo Bay is set to depart Tuesday

The Trump administration on Tuesday began flights transporting "criminal aliens" to Guantanamo Bay, with plans in the works to use the Cuban detention facility to eventually hold thousands of other migrants.

As tents went up in Guantanamo Bay, Cuba to hold migrants, attorneys at the Department of Homeland Security and Pentagon were still trying to determine whether it was legal to take the unprecedented step of flying migrants from the US southern border to the facility,

The first flight carrying migrants to Guantanamo Bay is en route and will arrive Tuesday evening, a U.S. Transportation Command official said.

The U.S. government is moving quickly to implement President Trump's order to turn facilities at the Guantanamo Bay Naval Base into a large-scale immigration detention center.