PESHAWAR, Pakistan — A court in Pakistan on Saturday reduced by 10 years the jail term handed down to a Pakistani doctor who helped the United States track down al Qaeda leader Osama bin Laden, in a blow to his supporters who have been fighting for his release.

Shakil Afridi, hailed as a hero by U.S. officials, was arrested after U.S. soldiers killed bin Laden in May 2011 in a raid in a northern Pakistani town that outraged Pakistan and plunged relations between the strategic partners to a new low.

Pakistan arrested Afridi and sentenced him to 33 years in jail for being a member of a militant group, a charge he denies.

On Saturday, a court in the city of Peshawar reduced his sentence to 23 years following repeated calls by the United States and his legal team for his release.

"We will receive a complete court order on Monday and will then challenge it at the FATA Tribunal," said Afridi's lawyer, Qamar Nadeem, referring to a higher tribal court.

Afridi has become a new irritant in the complex ties between Washington and Islamabad that have been deteriorating over past years despite Pakistan's pivotal role to U.S. interests in Afghanistan, counter-terrorism and nuclear security.

The day after Afridi was sentenced, the U.S. Senate expressed its anger by voting to dock Islamabad $33 million in aid - $1 million for every year of the term.

Pakistan has accused the doctor of running a fake vaccination campaign in which he collected DNA samples to help the U.S. Central Intelligence Agency track down bin Laden.