WASHINGTON: President Barack Obama on Monday announced his choice of Chuck Hagel as his next defense secretary and counterterrorism adviser John Brennan to lead the Central Intelligence Agency, two potentially controversial picks for his second-term national security team.      

Hagel has faced tough criticism from congressional Republicans who say the former Republican senator is anti-Israel and soft on Iran. Brennan, a 25-year CIA veteran, withdrew from consideration for the spy agency's top job in 2008 amid questions about his connection to criticized interrogation techniques during the George W. Bush administration.

Brennan's nomination also will draw attention to the highly secretive US drone program, which is highly unpopular overseas. He was the first Obama administration official to publicly acknowledge the targeted killing operations.

Obama called Hagel ''the leader that our troops deserve'' and said both men understand that ''the work of protecting our nation is never done.''

Along with secretary of state nominee Sen. John Kerry, Hagel and Brennan would play key roles implementing and shaping Obama's national security priorities. All three must be confirmed by the Senate.

In nominating Hagel, Obama signaled he is willing to take on a tough confirmation fight. The 66-year-old moderate Republican has criticized discussion of a military strike by either the US or Israel against Iran. He also irritated some Israel supporters with his reference to the ''Jewish lobby'' in the United States. And he has backed efforts to bring Iran to the table for future peace talks in Afghanistan.

The second-ranking Senate Republican, John Cornyn, said in a statement that making Hagel defense secretary would be ''the worst possible message we could send to our friend Israel and the rest of our allies in the Middle East.''

White House officials say Hagel's positions on Israel and Iran have been misrepresented. They cite his Senate votes for billions in military assistance to Israel and his support for multilateral sanctions on Tehran.

Ben Rhodes, Obama's deputy national security adviser, said Hagel will be ''completely in line with the president'' on both issues.

'The president has a record of unprecedented security cooperation with Israel, and that's going to continue no matter who the defense secretary is,'' Rhodes said.

Hagel has also been criticized by some Democrats for saying in 1998 that a nominee for an ambassador post was ''openly, aggressively gay.'' He has since apologized for those comments.

Hagel is the second straight Obama favorite for a top national security post to face criticism from lawmakers even before being nominated. United Nations Ambassador Susan Rice withdrew her name from consideration for secretary of state amid charges from Republican senators that she misled the public in her initial accounting of the deadly attacks on Americans in September at a diplomatic post in Benghazi, Libya.

Both Hagel and Brennan have close relationships with Obama, who values loyalty in his inner circle. Brennan, as the president's top counterterrorism adviser, was deeply involved in the planning of the 2011 raid that killed Sept. 11 mastermind Osama bin Laden. And he has led administration efforts to quell the growth of terror organizations in Yemen and elsewhere in the Middle East and North Africa. Brennan, 57, spent a quarter-century at the CIA. He served as station chief in Saudi Arabia and in a variety of posts, including deputy executive director, during the Bush administration.

His tenure at the agency during Bush's presidency drew criticism from liberals when Obama considered naming him CIA director after the 2008 election. Brennan denied being involved in what the government called ''enhanced interrogation techniques'' during the Bush administration but still withdrew his name from consideration.

In a letter to Obama at the time, Brennan said he was ''a strong opponent of many of the policies of the Bush administration, such as the preemptive war in Iraq and coercive interrogation tactics, to include waterboarding.'' Many people consider waterboarding and other harsh interrogation methods to be torture.

White House officials say they don't expect Brennan to face similar trouble this time, given his four years of service in the Obama administration.  ''The issue has been removed from the debate because the president and John Brennan, as his top counterterrorism adviser, brought those techniques to an end,'' Rhodes said.

However, Brennan's nomination will likely put a spotlight on the administration's controversial drone program. Brennan has defended the legality of the overseas drone operations and has said they protect American lives and prevent potential terror attacks.

If confirmed, Brennan will succeed David Petraeus, who resigned in November after admitting to an affair with his biographer.