Following intense US lobbying for action against Iran, the 35-nation governing board of the International Atomic Energy Agency (IAEA) passed a resolution on Friday demanding Iran answer all outstanding questions about its nuclear program.

The resolution implies that if the IAEA still has doubts about Iran's atomic program in November, its board might declare Iran in breach of international obligations and report it to the UN Security Council for possible economic sanctions.

Approval of the resolution ignited the wrath of Tehran. Iran's ambassador to the IAEA in Vienna, Ali Akbar Salehi, said it showed Washington intended to invade Iran as it had Iraq.

In an interview in the German weekly Der Spiegel, he expressed anger at US desires to stop Iran from enriching uranium, due to Washington's fears Tehran might be purifying it for use in a bomb.

The resolution calls on Iran to suspend all uranium enrichment activities for the time being and not to introduce uranium to its enrichment plant at Natanz.

"We could at first limit our cooperation with the IAEA to a minimum, to that which we have committed ourselves," Salehi said in the interview, which Der Spiegel said took place on Wednesday, a day after a draft of the tough resolution was tabled.

"We could also put a stop to cooperation. And as a last measure, I cannot rule out that we could withdraw from the Nuclear Non-Proliferation Treaty (NPT)."

Surprisingly, Russia -- which diplomats said had fought hard to weaken the US-backed language of the resolution to protect billions of dollars of future nuclear deals with Tehran -- threw its political weight behind the deadline and publicly backed it.

"(The resolution) is a serious and respectful appeal by the agency for Iran to cooperate with IAEA...and do so without delay," Deputy Foreign Minister Sergei Kislyak told Interfax.

If Iran were declared in non-compliance with its IAEA nuclear Safeguards Agreement -- a key part of the NPT -- and reported to the Security Council for sanctions, Tehran could lose the right to any foreign nuclear assistance.

That means Russia would lose out on a nearly $1 billion deal to construct the Bushehr nuclear power plant in Iran.

Tehran denies US allegations that it has violated the NPT in an effort to develop atomic weapons secretly.

But Anoush Ehtesami, professor of international relations at Britain's University of Durham, said some in Iran's military wanted to quit the NPT and follow Pakistan and India's example.