The self-proclaimed mastermind of the 11 September 2001 attacks on the US probably will remain in military detention without trial for the foreseeable future, the Washington Post reported yesterday, citing Obama administration officials.

The administration has concluded it cannot try Khalid Sheikh Mohammed in federal court in New York because of opposition from members of Congress and local officials. There is also little support in the administration for a military prosecution at Guantánamo Bay over concerns it would alienate liberal supporters.

Mohammed was captured in Pakistan in 2003 and has been imprisoned at Guantánamo. The administration asserts it can hold Mohammed and other accused al-Qaeda operatives under the laws of war.

Attorney general Eric Holder said last week he was close to deciding where Mohammed would be tried and whether he would face a military tribunal. Holder's plan to try Mohammed and four other accused plotters in New York was put on hold after officials and lawmakers raised security concerns.