British officials recently rejected a U.S. offer to transfer 10 former British residents from Guantanamo to the United Kingdom, arguing that it would be too expensive to keep them under surveillance, the newspaper said, citing documents made public this month in London.
Britain has also staved off a legal challenge by the relatives of some prisoners who sued to require the British government to seek their release, The Washington Post said.
While all British citizens in Guantanamo were freed starting in 2004, Britain has balked at allowing former legal residents of the country to return, the newspaper said.
Germany and other European allies, which have spoken out against Guantanamo, also have balked at accepting prisoners from the facility, the Post said.