Senator John McCain (R-AZ)speaks while Senator Kelly Ayotte (R-NH) listens during a press conference on Capitol hill January 13, 2015 in Washington. (Agence France-Presse)
US Senate Republicans including John McCain introduced a measure Tuesday that temporarily halts transfers of most of Guantanamo's war-on-terror detainees, saying the releases only lead to more attacks.
McCain joined ally Senator Kelly Ayotte in support of her legislation that would put a two-year moratorium on international transfers of detainees determined to be medium or high risk, as well as a two-year halt to all transfer of Yemeni detainees.
Of the 127 men remaining behind bars at Guantanamo, 81 are from Yemen.
Ayotte said a time-out on the releases was needed, particularly after the deadly attacks last week in France, where authorities determined that one of the Islamist extremist suspects earlier had been jailed but released.
"We shouldn't just release them back out in this security setting that they could come back and attack us again," Ayotte told reporters.
She said "the overwhelming majority" of remaining Guantanamo detainees have been determined to be medium or high-risk.
President Barack Obama has pledged to close the US prison camp in Cuba, where US authorities have been speeding up releases as they aim to finally shut the facility that opened 14 years ago, months after the September 11, 2001 terror attacks on the United States.
But "he hasn't made his case to the American people," said Ayotte.
The legislation is expected to make its way to the Senate Armed Services Committee, where McCain is chairman.
He said there was no firm date for debating the bill, but stressed there was strong Republican support in the House, which like the Senate is controlled by Republicans.
"We know for a fact that roughly 30 per cent of those who have been released (from Guantanamo) have re-entered the fight, and usually at a very high level because it's a badge of honor to have been an inmate at Guantanamo Bay," McCain said.
The senator, himself a former prisoner of war, has said he is willing to consider any Obama plan to responsibly shutter Guantanamo.
"But in over six years, this administration never presented a concrete or coherent plan," he fumed.
Hawkish Senator Lindsey Graham said events in France highlighted the need to keep terror-war detainees in jail -- some for the rest of their lives -- and not release them even under close supervision.
"The idea that you can release these people and watch them has a hole in it," Graham said. "Monitoring has its limitations."
Ayotte's bill extends for two years the prohibition on transferring Guantanamo detainees to US soil, and prohibits construction of facilities to house such detainees in the United States.