TOKYO (Kyodo) -- Hiroshima Mayor Kazumi Matsui on Friday urged Prime Minister Shigeru Ishiba to decide on Japan's participation as an observer at a meeting in March of signatories to the U.N. nuclear ban treaty.

During their meeting at the prime minister's office, Ishiba remained elusive, quoted by Matsui as saying that "various discussions are necessary" on what the country's approach should be.

Japan is the only country to have experienced the devastation caused by atomic bombs -- one dropped by the United States on Hiroshima and the other on Nagasaki in the final days of World War II. It has long relied on the U.S. nuclear umbrella and is not a member of the Treaty on the Prohibition of Nuclear Weapons, which entered into force in 2021.

Matsui made the call, representing a nongovernmental group consisting of heads of municipalities in Japan and abroad pressing to rid the world of nuclear weapons. Nagasaki Mayor Shiro Suzuki also attended the meeting.

The group said in a letter handed to Ishiba that the winning of the Nobel Peace Prize by Nihon Hidankyo, Japan's leading group of atomic bomb survivors, sent out the message that the use of nuclear weapons should never be tolerated.

They urged Japan to sign the nuclear ban treaty to realize a world free of such weapons as soon as possible.

While sharing the need to rid the world of them, Ishiba has been noncommittal. When he met with Hidankyo members on Jan. 8, he did not clearly respond to their demand for Japan's participation in the upcoming meeting in New York in March.

The group, known as the Japan Confederation of A- and H-Bomb Sufferers Organizations, was awarded the Nobel Peace Prize for its work toward a nuclear-free world.