U.S. Secretary of State Hillary Clinton (R) and Japanese Foreign Minister Koichiro Gemba shake hands after a joint press conference at the State Department, in Washington D.C., the United States, on April 10, 2012. U.S. Secretary of State Hillary Clinton on Tuesday urged the Democratic People's Republic of Korea (DPRK) to drop its planned satellite launch, terming the move as a threat to regional security. [Xinhua]