U.S. President Barack Obama said he will engage actively with enemies as well as friends to resolve nuclear threats and pledged to use power in a legitimate manner to regain U.S. global credibility, tarnished by the war in Iraq.
Obama, the first African-American President, made the remarks at a swearing-in ceremony on the steps of the U.S. Capitol.
"With old friends and former foes, we will work tirelessly to lessen the nuclear threat, and roll back the specter of a warming planet," Obama said, referring to the nuclear threats from North Korea and Iran.