President of the United States of American Barack Obama has nominated Senator John Kerry to succeed Hillary Clinton as his next secretary of state. Obama said Kerry's "entire life" prepared him for the role, and praised him for the respect and confidence he has earned from world leaders. His nomination comes after the US ambassador to the UN, Susan Rice, withdrew from consideration last week. Republicans had fiercely criticised her role in the aftermath of the deadly attack on the US consulate in Benghazi, Libya, in September. Kerry ran as Democratic presidential candidate in 2004 and is chairman of the Senate Foreign Relations Committee.