Publicly disclosing details of joint U.S.-British intelligence operations to target and kill suspected Islamic militants in Pakistan and elsewhere would "have [a] significant impact" on future cooperative efforts between the two world powers, James Eadie, lawyer for UK Foreign Office, said Thursday.
"That impact would be felt in an acutely controversial, sensitive and important context," he added.
Noor Khan, a Pakistani national, has requested the court investigate the role British intelligence played in a March 2011 U.S. drone strike that killed his father, Malik Daud Khan, in northwest Pakistan.
Khan claims his father was one of 40 Pakistanis killed when U.S. drones mistakenly attacked a meeting of local elders in the dangerous North Waziristan region along the Afghan-Pakistan border.
As part of the inquiry, the court is exploring the possibility of criminal charges against the British intelligence agents who allegedly provided the target coordinates to CIA officials who carried out the drone strike last March.
The court's ruling on whether to call official hearings into the matter is expected by the end of the year, U.K. officials tell the AP.
U.S. intelligence officials have been wary about sharing sensitive intelligence with the U.K. ever since a 2008 court case forced the British government to disclose specific details on terror detainee operations.
Binyam Mohamed, a U.K. national, sued and won the release of sensitive documents related to his four-year imprisonment at American detention facility in Guantanamo Bay, Cuba, from 2004 to 2009.
In 2010, the U.K. courts ordered the documents held by MI5 and MI6, the British domestic and foreign intelligence services, to be made public as part of the case.
That ruling has had a significant chilling effect on ties between MI5, MI6, CIA and the rest of the American intelligence community.
Ken Clarke, the United Kingdom's justice secretary, said in April that U.S. intelligence agencies are keeping their British counterparts in the dark, out of fear those secrets could end up on full display in U.K. courts.
“The Americans have got nervous that we are going to start revealing some of the information and they have started cutting back, I’m sure, on what they disclose," Clarke said in an interview with the BBC at the time.