WASHINGTON: A US senator has blocked the nomination of the American ambassador to Pakistan as part of his effort to put pressure on Islamabad to release Dr Shakil Afridi, diplomatic sources told Dawn.

Pakistani lobbyists on Capitol Hill came to know about the move on Thursday evening but it was confirmed only when a correspondent of the Foreign Policy Cable network reached Senator Rand Paul.

The Kentucky Republican confirmed that he had objected to the nomination, pushing off Ambassador Richard Olson’s confirmation until at least September.

The lawmaker explained that his hold on the nomination was part of his strategy to pressurise Pakistan to release Dr Afridi, who helped the CIA locate Al Qaeda leader Osama bin Laden in Abbottabad.

In June, a court in Pakistan sentenced Dr Afridi to 33 years in jail for treason.

Senator Paul is also threatening to force a vote in the US Senate to cut all aid to Pakistan over the issue.