John Brennan was confirmed as CIA director on Thursday afternoon by a vote of 63-34.
His appointment followed a filibuster by Republican Senator Rand Paul, who spoke for almost 13 hours on the Senate floor calling for more information about the Obama administration’s drone policy, CNN reported.
While Brennan's appointment was widely predicted, he faced opposition from critics including Senator Paul who delayed the vote and demanded clarification from President Barack Obama's administration that it would not use unmanned drones to kill American citizens on US soil, the Washington Post reported.
Paul, who led the marathon session that officially ended Thursday afternoon, said he was satisfied with a response from the Justice Department.
More from GlobalPost: Brennan advances as 'drone wars' controversy heats up
Brennan, who has long served as the president's top counterterrorism official, has been a top architect of the Obama administration's drone program.
He was grilled on the program during confirmation hearings, along with his stance on torture methods that were used during the administration of former President George W. Bush, CNN reported.
He served in top intelligence posts under both Bush and President Obama, the New York Times reported.
Brennan replaces retired General David Petraeus and acting CIA Director Michael Morell.