Military action against Iran would backfire against Israel, which in turn would face "dire and far-reaching" consequences, a leading British foreign policy think-tank believes.
Chatham House says in a report that it is "widely assumed" that preparations are "well under way" in both America and Israel for military action against targets related to Iran's nuclear programme. The report by Yossi Mekelberg examines the possible responses by Iran, which may retaliate with massive ballistic missile attacks on Israeli cities such as Tel Aviv or Haifa, resulting in "substantial loss of life".
Israel's relations with moderate Arab states would also be harmed, as any military attack would be seen as an offensive against the Muslim world and would fuel Islamic extremism.
"An Israeli military operation against Iran would hurt Israel's long-term interests. It would be detrimental to Israel's overall security and the political and economic consequences would be dire and far-reaching," the report warns.
Israel says the issue of curbing Iran's suspected nuclear weapons programme is a problem for the international community. But it has been made clear by the Prime Minister, Ehud Olmert, that if the international community failed to prevent Iran from obtaining a weapon, Israel would take the steps to do so.
While the report describes such a possibility as remote, it says that if diplomatic efforts fail, "the US and Israel would feel that force is justified and might act militarily either together or separately, regardless of international consent. This could have disastrous consequences."
Mr Mekelberg concurs with other analysts who have warned that military action against Iran could provoke fallout against US forces in Iraq. And like previous studies, the report points out that any attack would be unlikely to halt Iran's nuclear programme, and would only delay it "for a while."
The report concludes that international efforts should continue to focus on diplomatic and economic sanctions that could persuade the Iranian authorities to comply with UN demands. The report argues that Israel could consider open deterrence by coming clean on its nuclear arsenal as an alternative to military action, an option the Israelis are unlikely to contemplate.
The UN Security Council is calling on Iran to halt uranium enrichment - which can produce fuel for a nuclear weapon - in return for negotiations. But Iran, which says its intentions are peaceful, defied a deadline which passed last month, exposing Tehran to expanded sanctions.
Iranian state-run television said that President Mahmoud Ahmadinejad wanted to brief the UN Security Council about his country's nuclear plans, but did not give further details.