A federal appeals court has denied a bid by Jonathan Pollard, who served prison time for leaking U.S. intelligence information to Israel more than 30 years ago, to alter the terms of his parole.

Pollard served 28 years in prison for conspiracy to deliver national defense information to a foreign government and was released in 2015.

Pollard, who was a civilian intelligence analyst for the Navy at the time of his offense, argues that the information he leaked was vital to Israel's security but that it was being deliberately withheld.