Obama Sworn in as 44th U.S. President        1/20/2009 10:33:53 PM

By Tuesday afternoon, the world had greeted the new U.S. leader with positive responses. The European Union's Czech presidency issued a statement to warmly welcome Obama's inauguration, saying it "creates new encouraging perspectives and opportunities" for the further promotion of transatlantic relations. Russian Foreign Minister Sergei Lavrov said that his country will boost relations with the United States if equal security will be guaranteed.

Some major countries, including China and Japan, are yet to make responses as they remain in sleeping hours.

Shortly before the Obama swearing-in, 66-year-old Joe Biden, a former Delaware senator, took the oath of office as U.S. vice president, administered by John Paul Stevens, associate justice of the Supreme Court.

Following the inauguration on the U.S. Capitol, Obama's predecessor George W. Bush and his wife Laura boarded a helicopter and headed to the Andrews Air Force Base. The Obama couple, in keeping with the tradition, escorted them to the helicopter and saw them off.

The former president, who concluded his two turbulent terms with record low approval ratings, will fly to Midland, Texas, where he had spent his early years as a child.