Iran's newly disclosed nuclear fuel facility will soon become operational, an aide to Supreme Leader Ayatollah Ali Khamenei was quoted as saying on Saturday.

The statement came a day after U.S. President Barack Obama demanded that Iran come clean about its nuclear program or face "sanctions that bite" after the disclosure of the new uranium enrichment plant under construction south of Tehran.

"This new plant, God willing, will soon become operational and will make the enemies blind," Mohammad Mohammadi-Golpayegani, who heads Khamenei's office, said, according to the semi-official Fars News Agency.

Mohammadi-Golpayegani, a cleric, said the construction of the plant was a sign of Iran being at the "summit of power," Fars reported. He was speaking at a ceremony marking the start of the 1980-88 Iran-Iraq war.

Ahmadinejad: Israel wouldn't dare attack Iran

Meanwhile Friday, Iranian President Mahmoud Ahmadinejad said that Israel "will not dare attack Iran" and that if Israel does, "the Iranians can defend themselves."

"We are not concerned [about an Israeli attack]. Iran is a very big country. Much larger and bigger than what some people think and imagine," Ahmadinejad told a news conference.

Ahmadinejad's statement came hours after he said the United States, Britain and France would "regret" accusing Iran of hiding a nuclear fuel facility, saying it was not a secret site.

Ahmadinejad, speaking at a New York news conference, said Iran had informed the International Atomic Energy Agency early about the facility, which the Western leaders on Friday labeled a direct challenge to the international community.

"It's not a secret site. If it was, why would we have informed the IAEA about it a year ahead of time," Ahmadinejad said. "They [the United States, Britain and France] will regret this announcement."

The statement came after Ahmadinejad said Iran was not obliged to tell the Obama administration of every uranium enrichment plant it has, turning up the heat in a dispute over Tehran's nuclear program.

"This does not mean we must inform Mr. Obama's administration of every facility that we have," he told Time magazine in an interview when asked about Obama's charge that a nuclear fuel plant had been built secretly.

"We have no secrecy, we work within the framework of the IAEA," Ahmadinejad told Time in a reference to the UN nuclear watchdog, the International Atomic Energy Agency.

Ahmadinejad's comments came after U.S. Secretary of State Hillary Clinton said the IAEA must investigate Iran's newly disclosed uranium enrichment plant and Tehran must take immediate steps to show its program is peaceful.

"This is now a clear challenge to the international community," Clinton told reporters in New York after Iran told the IAEA it had a second uranium enrichment plant under construction. The disclosure by Iran came just as six world powers and Iran prepare for rare talks on Oct. 1.

"This facility sharpens our sense of urgency and underscores Iran's absolute need to engage seriously with us on October 1 and take immediate steps to demonstrate the exclusively peaceful nature of their nuclear program," she said after a meeting with Belgium's foreign minister.

Senate Foreign Relations Committee Chairman John Kerry released a statement following the revelation of the second plat, saying "In light of Iran's continuing deception, the international community must step up its demands that Iran halt its enrichment and reprocessing work."

Following the revelation of a second uranium enrichment plant in Iran, House Republican Whip Eric Cantor issued the following statement:

"Iran is a real-time security threat to the United States, Israel, and our allies around the world. A nuclear Iran is closer than many thought it was yesterday, and the problem is getting worse by the day, not better.

"The existence of a second uranium enrichment facility not only undercuts the Administration's policy toward Iran, but leaves little doubt that terrorist nations are not to be trusted or negotiated with diplomatically. Congress should act immediately to give the President the tools he needs to implement sanctions on Iran by passing the bipartisan Iran Refined Petroleum Sanctions Act."

House Republican Whip Eric Cantor issued a statement Friday saying Iran "is a real-time security threat to the United States, Israel, and our allies around the world. A nuclear Iran is closer than many thought it was yesterday, and the problem is getting worse by the day, not better."

Cantor added, "The existence of a second uranium enrichment facility not only undercuts the Administration's policy toward Iran, but leaves little doubt that terrorist nations are not to be trusted or negotiated with diplomatically."

Russia: Revelation of Iranian facility disturbing

Russian President Dmitry Medvedev on Friday urged Iran to prove it is not seeking to develop atomic weapons, stepping up pressure on Tehran and signaling increased solidarity with Western nations determined to rein in its nuclear program.

Medvedev said revelations that Iran has secretly been building a uranium-enrichment plant raised serious concerns, and demanded Tehran come to the table at an international meeting next week with a cooperative attitude and evidence of peaceful intentions.

"We are counting on Iran - particularly in light of the newly revealed information about the construction of a new enrichment plant - to provide convincing evidence of its intention to seek to develop nuclear energy with purely peaceful aims," Medvedev said in the statement.

His remarks, in a statement released during a G-20 summit overshadowed by worries over Iran, added to indications that Russia could support tougher sanctions if Tehran fails to comply with demands it come clean and halt uranium enrichment. But Medvedev did not mention sanctions or any other consequences Iran could face if it refuses to fall in line.

Medvedev said the undeclared construction of an enrichment facility flies in the face of UN Security Council demands for Iran to stop uranium enrichment at its only declared enrichment facility. He suggested the UN nuclear agency should take steps immediately to investigate the second site and called for Iran's full cooperation with the probe.

"The revelation about the construction of a second facility only strengthens our determination to achieve concrete and verifiable results in the years-long international efforts for clarity on Iran's nuclear program and its goals," Medvedev said.

Medvedev's new tone may raise U.S. hopes for a significant shift in Russia's stance on Iran. But Moscow may not go far beyond sanctions - and may again use its clout to ensure the punitive measures aren't too strong for its tastes.

Russia will only approve anctions that stop short of economic warfare or a military solution, Sergei Karaganov, Kremlin-connected head of the Council for Foreign and Defense Policy, an advisory body, said in an interview with The Associated Press.

Medvedev stressed that Russia is committed to a serious dialogue with Iran and the meeting is a chance for Tehran to show it is determined to seek a negotiated solution to the dispute over its nuclear program - another hint that Moscow could support new sanctions if that doesn't happen.

China responded to news of the secret neactor by saying that they hope Iran "will cooperate with the IAEA on this matter."

Egypt warns of Mideast nuclear arms race Egypt's foreign minister is warning that a nuclear-capable Israel and an Iran pursuing nuclear weapons could trigger a nuclear arms race in the Middle East.

Ahmed Aboul Gheit said in an interview Friday with the Associated Press that Iran has a right to the peaceful use of nuclear energy but it must be verified by the UN nuclear agency.

If the existence of a new uranium plant was kept secret, he said, that would shed doubts on the credibility of Iran's claim that its nuclear program was purely peaceful.

Aboul Gheit said Israel is assumed to possess nuclear weapons, and if Iran is also acquiring a nuclear capability many countries in the Middle East would be uneasy, triggering an arms race.

In the case of Iran, Aboul Gheit said, "one has to verify ? is it a peaceful nuclear effort or (if) it has an objective beyond."

"If it has an objective beyond, of course, Egypt very much objects to the introduction of nuclear weapons to this part of the world," he said.

"I hope that we would manage to verify that the Iranians are not going nuclear militarily," he said.

Aboul Gheit recalled that Egypt and Iran started pressing for the Middle East to be a nuclear weapons-free zone in 1974, and the two countries presented draft resolutions to the U.N. General Assembly for years calling for the establishment of such a zone.

If it turns out "that there is a military component for that Iranian nuclear project, then that would complicate very much the situation in the Middle East," he said.

Asked whether Iran's suspected nuclear ambitions and Israel's suspected nuclear arsenal could trigger an arms race by other countries in the Middle East to get nuclear weapons, in spite of calls for a nuclear weapons-free zone, Aboul Gheit replied: "Yes, and I'm of that view."

"Why is it so?," he asked. "Because if we have, what we assume a nuclear capable Israel and if we see that Iran is also ... acquiring a nuclear capability, then we would have two players in that part of the world, one on the Mediterranean, Israel, and the other on the (Persian) Gulf."

"So you would see, and you would find that you have a land mass of Arab countries and Arab people that do not feel at ease with that setting," Aboul Gheit said. "I would feel that the Turks would also be uneasy like a country like Egypt."

He wouldn't speculate how Egypt might respond.

"But the situation would be uneasy and it would trigger an arms race, no doubt about it," Aboul Gheit said. "Experience has taught us that you introduce one weapon, somebody else will try to acquire always that weapon."