US President Barack Obama is to nominate John Brennan as the director of the Central Intelligence Agency, White House officials have said, reports BBC.

If confirmed, Mr Brennan will replace Gen David Petraeus, who resigned last year after admitting to an affair.

Chuck Hagel is to be put forward as the president's next defence secretary, replacing Leon Panetta.

Both appointments are expected to be formally announced and must be confirmed by the Senate.

Mr Brennan, a CIA veteran, is currently Mr Obama's chief counter-terrorism adviser. He was heavily involved in the planning of the 2011 raid that killed Osama bin Laden.

Although put forward for the role in 2008, Mr Brennan withdrew his name amid questions about his connection to interrogation techniques used during the administration of George W Bush.

Mr Hagel, a moderate Republican senator from Nebraska, has faced criticism from some fellow Republicans who say he is hostile to Israel and soft on Iran. He has criticised discussion of a military strike by either the US or Israel against Tehran.