Iran's president Mahmoud Ahmadinejad has threatened Israel with destruction should it intervene in Lebanon again.

In a tough speech at Isfahan, broadcast on state television, he told the Israelis that the region would "cut the root of the Zionist regime from its stem."

Ahmadinejad also spoke about recent violence in the Gaza strip. Addressing Israel he said: "If you think that by bombing and assassinating Palestinian leaders, you are preparing ground for new attacks on Lebanon in the summer, I am telling you that you are seriously wrong."

The angry speech came as the U.N. nuclear watchdog warned that Iran could be as little as three years away from a nuclear weapon.

The report has caused the U.N. Security Council to impose a third round of sanctions on Tehran for its lack of transparency in what Iranian leaders insist is a peaceful nuclear program.

US and Iranian diplomats are due to hold direct talks in Baghdad on how to stabilize Iraq.

Nuclear weapons won't be part of the official talks but,in the meantime, the Pentagon has sent two aircraft carriers and seven other warships to the Persian Gulf as a show of force.