US President Barack Obama has said a Yemen-linked plot to bomb an airliner will not prevent the closure of the US prison at Guantanamo Bay.
The US has suspended the repatriation of Yemeni prisoners held there in the wake of the plot, claimed by a Yemen-based al-Qaeda offshoot.
Nearly half of those remaining at the detention centre at Guantanamo Bay, Cuba, are from Yemen.
Mr Obama originally set a January 22 deadline to close the prison camp.
But he admitted last November that that deadline had slipped to later in 2010.
Officials fear that Yemenis released from Guantanamo and sent back to Yemen could rejoin militant groups.
"It was always our intent to transfer detainees to other countries only under conditions that provide assurances that our security is being protected," Mr Obama said on Tuesday, during a briefing on security reviews ordered after the airliner plot.
"With respect to Yemen in particular, there's an ongoing security situation which we have been confronting for some time, along with our Yemeni partner."
But Mr Obama said the camp would still be shut, "in a manner that keeps the American people safe and secure".
"Make no mistake, we will close Guantanamo prison, which has damaged our national security interests and become a tremendous recruiting tool for al-Qaeda," he said.
"In fact, that was an explicit rationale for the formation of Al-Qaeda in the Arabian Peninsula."
A 23-year-old Nigerian, Umar Farouk Abdulmutallab, is accused of trying to bomb a US plane on 25 December over the US city of Detroit.
The plot was claimed by Al-Qaeda in the Arabian Peninsula (AQAP), which is based in Yemen, and the suspect was allegedly trained in the Middle Eastern country.
It was alleged last week that the bomb plot was planned by two men who were released by the US from Guantanamo Bay in November 2007.
Earlier, White House spokesman Robert Gibbs said: "While we remain committed to closing the facility, the determination has been made that right now, any additional transfers to Yemen are not a good idea."