Joseph S. Nye, a Harvard University professor who has authored several influential reports on Japan-U.S. relations, has been asked to be the next ambassador to Japan, sources said Wednesday.

Nye, 71, is chairman of the board of governors of the Honolulu-based Pacific Forum CSIS, a nonprofit foreign policy research institute that operates as the Asia Pacific arm of the Washington, D.C.-based Center for Strategic and International Studies.

Nye is a professor at, and former dean of, Harvard's Kennedy School of Government.

Analysts said the work on picking an ambassador to Japan before President-elect Barack Obama's inauguration on Jan. 20 indicates the importance that he places on ties with Japan.