U.S. President Barack Obama's choice for the next defense secretary, Leon Panetta, is testifying Thursday at a Senate hearing on his nomination.

The current head of the Central Intelligence Agency is addressing members of the Senate Armed Services committee.

If confirmed by the Senate, Panetta would take over the Pentagon at a time when President Obama has called for an additional $400 billion in cuts to defense spending.

The Associated Press news agency quotes Panetta as saying in a questionaire submitted to the Senate committee that everything in the defense budget “must be on the table ,” including possible changes to military pay and benefits.

AP quotes him as saying difficult choices must be made, based on the impact on national security.

Panetta would bring extensive budget experience to the Pentagon, having served as head of the White House budget office under President Bill Clinton, and before that, chairman of the House of Representatives Budget Committee.

Panetta is expected to be easily confirmed. The long-time Democrat would succeed Robert Gates, who plans to retire later this month.