The Senate Intelligence Committee vote on the nomination of John Brennan as CIA director is expected to take place Tuesday, a congressional aide said.

The vote had been scheduled for Thursday.

As President Barack Obama's chief counterterrorism adviser, Brennan was behind the use of drones to kill suspected terrorists, including American-born cleric Ansar al-Awlaki. He was killed by a missile strike in Yemen in 2011.

At his confirmation hearing, Brennan defended the use of drone strikes but acknowledged there should be more public discussion about them.