Iran had enriched uranium

"While I'm not in the position to confirm for you the technical details of what the Iranians may or may not have done, what I can say is that this is another step by the Iranian regime in defiance of the international community," U.S. State Department spokesman Sean McCormack said on Tuesday.

"Once again, they have chosen the pathway of defiance as opposed to the pathway of cooperation," he said.

"The international community is united in its conviction that Iran cannot be allowed to develop a nuclear weapon, that Iran cannot be allowed to possess the technology or the know-how to develop a nuclear weapon. One of the critical pathways to development of a nuclear weapon is the ability to enrich uranium to high levels," McCormack added.

Iranian President Mahmoud Ahmadinejad declared on Tuesday that Iran had officially joined the group of countries with nuclear capabilities commonly known as the Nuclear Club, Iran Focus News service reports.

"I officially announce that Iran has joined the world's nuclear countries," Ahmadinejad said in a speech that was broadcast on state television.

Earlier, Iran's nuclear chief announced that Tehran had recently managed to enrich uranium to the level required to make nuclear fuel.

"We successfully enriched uranium to 3.5 percent on April 9," Gholamreza Aghazadeh, who heads Atomic Energy Organisation of Iran, said.

McCormack said that there was a possibility that the international community would impose sanctions on Tehran for refusing to cooperate with the IAEA.

"If Iran continues down this pathway of defiance … you will see a parallel increase in the pressure on Iran from the international community," he said.

"We would call upon the Iranian regime to reconsider the steps that it has taken and to heed the call of the international community, the call of the U.N. Security Council and the IAEA Board of Governors to stop their enrichment activities, suspend them, come back into compliance with its international treaty obligations, come back into compliance with its previous obligations to the EU-3 and to engage the international community in a serious manner on this issue."

Asked why talks between Iran and the United States on the issue of Iraq had been postponed, McCormack said, "We did not think it was appropriate that while the process of government formation was ongoing in Iraq, that those discussions between the United States and Iran take place."

Meanwhile, White House Press Secretary Scott McClellan told reporters on Tuesday that Iran's statement that it had begun to enrich uranium using 164 centrifuges "only further underscores why the international community has serious concerns about the regime's nuclear ambitions".

"This is a regime that needs to be building confidence with the international community. Instead, they're moving in the wrong direction. This is a regime that has a long history of hiding its nuclear activities from the international community, and refusing to comply with its international obligations. Defiant statements and actions only further isolate the regime from the rest of the world, and further isolate the Iranian people," McClellan said.

Russia joined the United States on Wednesday in condemning Iran's announcement it had enriched uranium in defiance of a U.N. call to halt nuclear work that the West believes is part of a drive to build atomic bombs, Reuters informs.

Moscow, which has opposed using such measures against Iran, echoed the U.S. demand that Tehran halt enrichment activities.

"It goes counter to the decisions of the International Atomic Energy Agency (IAEA) and the statement of the U.N. Security Council," Russia's Itar-Tass news agency quoted a Foreign Ministry spokesman as saying of Iran's announcement.

He urged Iran to stop all uranium enrichment work, including research, but a senior Iranian official rejected this.

"Iran's nuclear activities are like a waterfall which has begun to flow. It cannot be stopped," said the official, who asked not to be named, when asked about Russia's demand.

Iran has traditionally regarded Moscow as a key nuclear ally and several officials in Tehran have predicted that Russia would veto any punitive action by the U.N. Security Council.

China on Tuesday urged a diplomatic solution.

"We still believe that negotiations and a diplomatic solution are the best way out of it," Wang Guangya, China's envoy to the United Nations, said in New York in comments carried by the official Xinhua news agency.

It was not immediately clear if Wang was responding directly to Iran's announcement.

In a well-flagged televised address, Ahmadinejad had said: "I am officially announcing that Iran has joined the group of those countries which have nuclear technology. This is the result of the Iranian nation's resistance."

"Based on international regulations, we will continue our path until we achieve production of industrial-scale enrichment," he told officials and some ambassadors from regional states gathered in the northeastern city of Mashhad.

The level of enrichment needed to trigger the nuclear chain reaction that detonates bombs is far higher than the 3.5 percent Iran says it has reached.

It would take Iran years to yield enough highly enriched uranium for one bomb with its current cascade of 164 centrifuges. But Tehran has told the IAEA it will start installing 3,000 centrifuges later this year, enough to produce material for a warhead in a year.

Japan will work with other countries to urge Iran to discontinue its uranium enrichment program, Chief Cabinet Secretary Shinzo Abe said.

"Japan will need to cooperate with the international community to firmly tell Iran it needs to ease global concerns" over its enrichment program, Abe said at a regular news conference in Tokyo today.

Oil traded near a seven-month high in New York on concern supplies from Iran, the world's fourth-biggest producer, may be disrupted by a confrontation over its nuclear program.

Abe added that oil prices are rising because of concerns over Iran as well as limited production capacity.

Crude oil for May delivery rose 1 cent to $69.00 a barrel in after-hours electronic trading on the New York Mercantile Exchange at 10:12 a.m. Singapore time. Prices today are 33 percent higher than a year ago, Trend reports.