A leader of a group of atomic bomb survivors in Japan has given a mixed reaction to Prime Minister Kishida Fumio's speech during the review conference of the Treaty on the Non-Proliferation of Nuclear Weapons.

Tanaka Terumi is the co-chair of the Japan Confederation of A- and H-Bomb Sufferers Organizations, or Nihon Hidankyo.

He spoke to NHK after Kishida became the first Japanese prime minister to deliver a speech at the NPT review conference, which was taking place in New York on Monday.

Tanaka said the speech wasn't bad, in that Kishida referred to the survivors' consistent desire to let the world know the true horrors of the atomic bombings.

But he said it is regrettable that the prime minister made no mention at all of the Treaty on the Prohibition of Nuclear Weapons.

He said he wanted Kishida to at least say that Japan is interested in the treaty, even though it may have been difficult for him to state that the country would ratify it.

UN Secretary-General Antonio Guterres said at the NPT conference that he will attend the peace memorial ceremony in Hiroshima on August 6 to mark the anniversary of the atomic bombing of the city in 1945.

Tanaka said he hopes Guterres will highlight the inhumane nature of nuclear weapons, promise in Hiroshima that the world will aim for the abolition of nuclear arms, and say that this is what the world wants to achieve.