The case is being brought by Britons held at Guantanamo Bay and in Afghanistan, who allege that Blair knew within several weeks after American troops rounded up terror suspects that British nationals detained by the United States were being tortured, The Guardian newspaper reported Tuesday.
Secret documents, which include 2002 documents between the Foreign Office and the Ministry of Defense's Security Service, revealed in Great Britain's high court in London show Blair was concerned about the detainees' treatment, The Guardian reported.
A note of Blair's read, "The key is to find out how they are being treated. Though I was initially skeptical about claims of torture, we must make it clear to the US that any such action would be totally unacceptable and quickly establish that it isn't happening."
The Guardian said there is evidence the British government knew the United States was torturing British nationals after January 2002 and for during ensuing years, but did not seriously protest it.
The high court heard Tuesday that security service officials continue to refuse to disclose information about when they were informed the United States had captured and imprisoned British nationals and residents before transporting them to Cuba's Guantanamo Bay prison, the Guardian said.
The litigation was filed by Binyam Mohamed, Bisher al Rawi, Jamil el Banna, Richard Belmar, Omar Deghayes, and Martin Mubanga against the security service, the attorney general, the Foreign Office and the Home Office, The Guardian said.