The mayor of Hiroshima plans to urge world leaders to reject the theory of nuclear deterrence at an upcoming event to mark the 78th anniversary of the atomic bombing of the city.

At a news conference on Friday, Mayor Matsui Kazumi presented the outline of the peace declaration he will read out at the August 6 ceremony.

In the declaration, the mayor looks back on the Hiroshima Vision on nuclear disarmament, which was issued at this year's Group of Seven summit in May.

Matsui is to note that the Hiroshima Vision espoused the view that nuclear weapons should, as long as they exist, only be utilized for defensive purposes.

He will urge world leaders to acknowledge that the theory of nuclear deterrence is no longer logical in light of a political leader's recent threats to use nuclear arms. He will ask them to face reality and reject the theory of nuclear deterrence.

The mayor says he will call on the Japanese government to sign and join the Treaty on the Prohibition of Nuclear Weapons, and to take part as an observer at the signatories' conference of the treaty to be held in November.

Matsui also plans to strongly urge the government to do more to support atomic bomb survivors.

The mayor told reporters on Friday that this year's peace declaration is drawing more attention than in years past, following the G7 summit in Hiroshima. He added he wants the declaration to be a strong appeal for peace from the atomic-bombed city.