Japan is reluctant to accept a proposal that urges the United States to limit the role of nuclear weapons to deterring only nuclear attacks and that seeks a commitment to never launching a first strike, sources said over the weekend.
Japan's representative to the International Commission on Nuclear Nonproliferation and Disarmament expressed reservations about the proposal due to concerns about the weakening of the U.S. nuclear umbrella, according to a draft report compiled by the panel, the sources said.
The commission, established at the initiative of Australia and Japan, aims to reinvigorate international nuclear nonproliferation and disarmament efforts. It is cochaired by former Foreign Minister Yoriko Kawaguchi and Gareth Evans, a former foreign minister of Australia.
The draft document envisages President Barack Obama working out a new nuclear doctrine before the review conference of parties to the nuclear nonproliferation treaty, which is scheduled to be held next May.
It says the "sole purpose of U.S. nuclear weapons is to deter use of nuclear weapons against the United States and its allies."