Washington, Jan 20 (IANS): The Pentagon announced that four more inmates were transferred out of the military prison in Guantanamo Bay, Cuba, marking the final such transfer under President Barack Obama and leaving the facility's population at 41.

Thursday's transfer concludes the Obama administration's final push to empty the facility as much as possible prior to President-elect Donald Trump's Friday inauguration, with 19 inmates being transferred since the November 8 Election Day, CNN reported.

One of the inmates is going to Saudi Arabia and the other three are being taken in by the United Arab Emirates (UAE), the Pentagon said.

There were 242 detainees at Guantanamo when Obama came into office in January 2009 and he had pledged to close the centre within one year in an executive order he signed shortly after his own inauguration.

But in recent days, administration officials have acknowledged that this goal was out of reach.

"I don't anticipate that we will succeed in that goal of closing the prison, but it's not for a lack of trying -- that, I assure you," White House Press Secretary Josh Earnest told a press briefing on Tuesday.

Earnest blamed both Republicans and Democrats in Congress for the administration's failure to close the detention facility.

The prison's peak population was 684 detainees in June 2003, CNN reported.

The Office of the Director of National Intelligence, which tracks recidivism among former inmates, said in a September report that nine of 161 inmates released since January 2009 had returned to supporting terrorist groups.

An additional 11 were "suspected" of having gone back to terrorist activity, though the report noted that the Defence Intelligence Agency puts that number at 15.