Capping more than three years of grueling negotiations, top Japanese and U.S. officials signed a set of agreements Monday in Washington to realign the U.S. military forces in Japan by 2014 and take the security alliance to a new level.

The agreements put the finishing touches on such thorny issues as the relocation of the U.S. Marine Corps' Air Station Futenma in central Okinawa and the transfer of some 8,000 marines from Okinawa to Guam.

The initiatives are part of the ongoing transformation of U.S. military forces worldwide to cope better with new security problems emerging after the Sept. 11, 2001, terrorist attacks in New York and Washington, while reducing host city burdens in Okinawa and elsewhere in Japan. They represent the first comprehensive shakeup of the U.S. military presence in Japan since the end of World War II.