Arab states and Israel plan to attend a rare round of talks next week on efforts to free the world of nuclear weapons but Iran has yet to say whether it will take part in the meeting in Vienna, diplomats said on Wednesday.

The November 21-22 forum, hosted by the International Atomic Energy Agency, is seen as symbolically significant in seeking to bring regional foes together at the same venue and start a dialogue, even though no concrete outcome is expected.

If conducted smoothly with toned-down rhetoric on both sides, it could send a positive signal ahead of a planned international conference next year on ridding the Middle East of nuclear and other weapons of mass destruction.

It is a good opportunity for everybody to sit and talk but

I don't think it is going to achieve a tangible result, a Western diplomat said.

Israel is widely believed to harbour the Middle East's only nuclear arsenal, drawing frequent Arab and Iranian condemnation.

Israel and the United States regard Iran as the region's main proliferation threat, accusing Tehran of seeking to develop a nuclear weapons capability in secret. An IAEA report last week added independent weight to those allegations.

Convened by IAEA chief Yukiya Amano, next week's discussions will focus on the experiences of regions in the world which have set up Nuclear-Weapons-Free Zones (NWFZ), including Africa and Latin America, and their possible relevance for the Middle East.

IAEA member states decided in 2000 that such a meeting should be held but until this year the parties involved were unable to agree on the agenda and other issues.

All 151 IAEA member countries have been invited to the talks, to be chaired by senior Norwegian diplomat Jan Petersen, but participating envoys from the region will be in focus.

NUCLEAR MEETING IN FINLAND

The forum will consider the experience of five NWFZs and two regional verification arrangements and discuss the potential relevance of such experience to the creation of a NWFZ in the Middle East, the IAEA said in a statement this week.

Diplomats said Israel and Arab states had accepted the invitation but that there had as yet been no word from Iran, which in September said it saw no justification for such a meeting now and took a swipe at arch-enemy Israel.

Israel, the only Middle East country outside the nuclear Non-Proliferation Treaty (NPT), has never confirmed or denied having nuclear weapons under a policy of ambiguity to deter numerically superior foes.

It says it would only join the NPT if there is a comprehensive Middle East peace with its longtime Arab and Iranian adversaries. If it signed the 1970 treaty, Israel would have to renounce nuclear weaponry.

Arab states, backed by Iran, say Israel's stance poses a threat to regional peace and stability.

Last month, the United Nations said Finland had agreed to host a potentially divisive international meeting in 2012 to discuss the possible creation of a Middle East free of weapons of mass destruction.

The idea for such a conference came from Egypt, which pushed for a meeting with all states in the Middle East to negotiate a treaty that would establish a nuclear arms-free zone.

Washington's commitment will be key to the success or failure of next year's talks, Western diplomats say, as it is the only state that can persuade Israel to attend.

(Editing by Mark Heinrich)