The Japanese government will not participate as an observer in a conference of the UN treaty banning nuclear weapons, which will be held next month in New York.

Foreign Minister Iwaya Takeshi explained the government's position on Tuesday.

He told reporters it would be difficult to take steps toward nuclear disarmament without the participation of nuclear-armed states, noting that none of them have joined the UN treaty.

He said it is preferable to continue efforts to achieve global nuclear disarmament under the Treaty on the Non-Proliferation of Nuclear Weapons, or NPT, which nuclear and non-nuclear states widely take part in.

Iwaya added that expanded nuclear deterrence is indispensable.

He explained that Japan taking part in the UN meeting could send "a wrong message" about the country's nuclear deterrence policy and "hamper efforts to secure peace and security."

Iwaya referred to this year marking 80 years since the atomic bombings during World War Two. He emphasized the government will work with survivors' groups and make practical efforts to abolish nuclear weapons within the NPT's framework.

Japanese Prime Minister Ishiba Shigeru had earlier said that he would consider whether to have his government join the New York meeting.

Nihon Hidankyo, a group representing survivors of the atomic bombings of Hiroshima and Nagasaki and last year's Nobel Peace Prize laureate, had requested the government to do so.

Nihon Hidankyo co-chair Tanaka Terumi expressed disappointment on the latest decision. He told NHK that the decent choice was to attend the meeting.

He said it would be a good opportunity for Japan to show its position. He said he had some hope, given that there is a new prime minister. He vowed to continue his appeal.

Japan's ruling Liberal Democratic Party and its coalition partner Komeito had initially considered sending both parties' lawmakers to the UN meeting to take note of the content of discussions.

But the LDP backtracked due to opposition from party members. Only Komeito will attend.