In an unusual diplomatic move, Japan may ask the United States during an upcoming bilateral summit to return to UNESCO as soon as possible, government sources said Saturday.

Prime Minister Junichiro Koizumi, who took office in late April, and U.S. President George W. Bush, who was inaugurated in January, will hold their first meeting at Camp David, Md., on June 30.

The U.S. bolted from the Paris-based United Nations Educational, Scientific and Cultural Organization at the end of 1984 under the Republican administration of President Ronald Reagan, citing mismanagement and other problems. Britain followed suit in 1985 but later rejoined the organization.