WASHINGTON (AFP) - Away from public view, US President Barack Obama on Wednesday (Nov 25) signed a defence Bill barbed with measures designed to undo his bid to close the prison at Guantanamo Bay.
In a terse statement, the White House said Mr Obama had signed the National Defence Authorisation Act for Fiscal Year 2016, along with several other pieces of legislation.
His signature significantly lengthens the odds that he will be able to close Guantanamo before leaving office in early 2017.
The Bill upholds a ban on transferring prisoners from Gitmo to the United States.
In a separate written statement, Mr Obama said he was "deeply disappointed that the Congress has again failed to take productive action towards closing the detention facility at Guantanamo".
He warned that his administration views some of the curbs on prisoner transfers as potentially unconstitutional.
Along with transfers to foreign countries, moving the most dangerous prisoners to a specialised facility in the United States is at the heart of the White House strategy to close Guantanamo.
Mr Obama came to office in 2009 vowing to shutter the facility that flashed images of caged men in orange jumpsuits being subjected to "enhanced interrogation" around the world.
"Maintaining this site, year after year, is not consistent with our interests as a nation and undermines our standing in the world," he said in a statement.
He has seen his efforts repeatedly thwarted by Congress.
In the latest setback, the White House has asked the Pentagon to look again at a masterplan to close the facility.
Whenever those measures are published, they are sure to face resistance in Congress.
But Mr Obama has so far been unwilling to commit to closing the facility by executive order, a move that would likely spark a political firestorm and multiple lawsuits.
"It is long past time for the Congress to lift the restrictions it has imposed and to work with my administration to responsibly and safely close the facility, bringing this chapter of our history to a close," he said.