Susan Rice

Susan Rice, U.S. ambassador to the United Nations, has been named as President Obama's next national security advisor. (Spencer Platt / Getty Images / February 12, 2013)

WASHINGTON -- Susan Rice will take over as President Obama's national security advisor this summer and longtime advisor Samantha Power will be named to take her position as U.S. ambassador to the United Nations, officials said Wednesday.

Tom Donilon is stepping down as national security advisor after four years as a member of the White House foreign policy team, White House officials said Wednesday. The president plans to unveil the national security appointments in the Rose Garden on Wednesday afternoon.

The changes would install two trusted advisors in key positions as Obama moves into a second term dominated by tough foreign policy challenges. Donilon is expected to leave his post early next month and Rice will take over as Obama launches a tour of the African continent.

Rice, 48, is a longtime adviser to the president who most recently came under fire from Republicans for her role in the controversy over the attacks in Benghazi. Republicans charge she intentionally downplayed the role of terrorist groups during an initial round of interviews after the attack on a diplomatic post in Libya last year.

The controversy killed her chances of becoming secretary of State, after key Republicans threatened to block her even before she was nominated. Rice will not need Senate approval to take the nation security advisor post.

Power, 42, has been an advisor to Obama since before the 2008 campaign and went on to serve as a special assistant to the president and senior director for multilateral affairs and human rights during his first term.

She won the Pulitzer prize for her 2002 book, “A Problem From Hell: America and the Age of Genocide.”

Donilon, 58, has been a part of Obama's national security staff for four years. After replacing Gen. James Jones as Obama's national security advisor in 2010, Donilon helped to craft the administration's policy for drawdown in Afghanistan and advised caution in the U.S. raid that killed Osama bin Laden.

A former chief of staff to Secretary of State Warren Christopher, Donilon has been a consistent voice for turning U.S. foreign policy focus to Asia. As one of his last acts before announcing his resignation, Donilon traveled to Beijing in May to help lay the groundwork for Obama's upcoming summit with Chinese President Xi Jinping.

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