US President George W Bush has urged Congress to back his proposals on the treatment of Guantanamo Bay detainees.
The measures are vital tools to protect the US, the president says
Mr Bush told reporters at a hastily arranged press conference that his controversial plans were essential for the protection of the United States.
He was speaking a day after four key Republican senators rebelled, backing an alternative draft proposal.
The dispute centres on what evidence against them detainees can see and what interrogation methods are allowed.
The Supreme Court ruled earlier this year that Mr Bush did not by himself have the authority to order detainees tried by military tribunal, as the administration had been planning.
The June verdict forced the White House to press Congress to pass a law governing the proposed trials.
But the Bush proposal has run into resistance from several top members of his own party, including ex-Secretary of State Colin Powell.
Mr Powell said in a letter made public on Thursday that the proposed changes could put US troops at risk.
But Mr Bush said they were essential in the so-called war on terror and to protect the US against attack.
He urged Congress to act "promptly and wisely" to back his measures.
"Were it not for this programme our intelligence community believes that al-Qaeda and its allies would have succeeded in launching another attack against the American homeland," he told reporters at a White House briefing on Friday.
Mr Bush said he would work with "members of both parties to get legislation that works".
But he warned that "time is running out", and urged Congress to pass a "clear law with clear guidelines" before it goes into recess in two weeks, ahead of November's mid-term elections.
Four Republican senators joined opposition Democrats on the Armed Services Committee on Thursday to endorse a alternative bill put forward by Republican John McCain.
The senators argued that Mr Bush's proposals would effectively redefine the Geneva Conventions to allow harsh treatment of detainees held at the Guantanamo Bay camp in Cuba.
They said their own version would provide fair trials and meet the demands of the US Supreme Court.
The senators are also worried about White House efforts to reinterpret Article Three of the Geneva Conventions in order to allow tougher interrogations of suspects.
The article in question governs detainee treatment - banning torture, violence and degrading treatment, and demanding that the sick and wounded are cared for.