Foreign Minister Taro Aso plans to visit the United States in late April for talks with U.S. officials ahead of a planned visit by Prime Minister Junichiro Koizumi in June, Foreign Ministry sources said Wednesday.

Aso appears to be trying to raise his profile as a potential successor to Prime Minister Junichiro Koizumi by making a side trip to San Francisco, where he plans to visit two historical sites that defined Japan’s postwar relationship with the U.S.

The late Prime Minister Shigeru Yoshida, Aso’s grandfather, signed the 1951 San Francisco peace treaty, which quickened the end of the Allied Occupation, at the San Francisco Opera House.