Senator John Kerry was in Islamabad yesterday to push for the release of Raymond Davis, an American consulate employee facing charges over two killings.
The United States insists Mr Davis has diplomatic immunity from prosecution. Mr Kerry assured the Pakistan government that Mr Davis would face a criminal investigation in the US upon his return.
A Pakistani official said the country's government believed Mr Davis was shielded by diplomatic immunity but could not overrule a court. Mr Davis shot dead two men he said were trying to rob him.