A day after US Secretary of State Hillary Rodham Clinton downplayed Iran's claim that it had developed new uranium enrichment technology, France expressed its concern over the assertion.
"These are worrying declarations," French Foreign Ministry spokesman Eric Chevallier told reporters. "We need to check the accuracy of the figures ... and for that we'll wait for the International Atomic Energy Agency."
Chevallier urged Teheran to submit to a full IAEA inspection regime at all its nuclear sites and halt its uranium enrichment program.
On Thursday, Iranian President Mahmoud Ahmadinejad announced advances in the country's nuclear program, including the inauguration of a new nuclear-related facility and the testing of two types of high-capacity centrifuges that he said would speed up Iran's enrichment capacity.
He also claimed that there were 7,000 working centrifuges to enrich nuclear fuel at Iran's Natanz facility.
Clinton said Thursday night the declaration would not affect the US decision to resume participation in international talks on the Islamic republic's nuclear program.
"We don't know what to believe about the Iranian program," she said, adding that the US government did not "attribute any particular meaning" to Iran's statement with respect to the negotiations.
An official in the Prime Minister's Office said Thursday night that Iran's pursuit of nuclear weapons "demands everyone's attention" and "must be of grave concern to every thinking individual."
The comment came two days after US Vice President Joe Biden said in a CNN interview that it would be "ill advised" for Israel to launch a military strike against Iran. Biden added that he did not believe Prime Minister Binyamin Netanyahu would take such a step.
The Obama administration announced Wednesday that it would participate directly in group talks set to start Saturday in Geneva with Iran over its nuclear program, another significant shift from president George W. Bush's policy toward a nation he labeled part of an axis of evil.
The State Department said the United States would be at the table "from now on" when senior diplomats from the five permanent members of the UN Security Council and Germany meet with Iranian officials to discuss the nuclear issue.
"We believe that pursuing very careful engagement on a range of issues that affect our interests and the interests of the world with Iran makes sense," Clinton told reporters. "There is nothing more important than trying to convince Iran to cease its efforts to obtain a nuclear weapon."
Meanwhile, the Japanese newspaper Nikkei reported Thursday that several Western intelligence organizations were investigating whether a ship that recently traveled from North Korea to Iran had several dozen tons of enriched uranium hidden in its cargo.
According to the report, the suspected move was seen by some intelligence officials as an effort to hide traces of the highly enriched uranium program to develop nuclear weapons, which the US believes North Korea is secretly pursuing.
According to one Western intelligence source, the ship in question left North Korea last December and traveled through the Indian Ocean. The cargo was then shipped to a location near Teheran.
"The bulk of the [transferred] materials appears to be medium-level enriched uranium," the source said. "It could be further enriched to weapons grade in Iranian facilities."
Western countries fear that there could be some kind of enrichment agreement between North Korea and Iran.
Ahmadinejad, meanwhile, said Thursday that Iran was open to talks offered by the US and other countries over its nuclear program, if the negotiations were based on "respect" for its rights.
Speaking at a ceremony to inaugurate the new facility producing uranium fuel for the planned heavy-water nuclear reactor in Isfahan, Ahmadinejad said that past negotiations had fallen apart because of the West's demands that Iran rein in its nuclear program.
He said "the Iranian nation has always been for talks," but that negotiations must "be based on justice and respecting rights."
The US and its allies have expressed concerns that Iran could reprocess spent fuel from the heavy-water reactor into plutonium for building a warhead.
The process is distinct from uranium enrichment, which produces fuel for a light-water reactor. Highly enriched uranium can be used to build a warhead as well. Iran's enrichment program presents more immediate concerns to the West than the hard-water reactor, because it is far more advanced.
The Defense Ministry said in a statement it was closely following the developments, stressing that the inauguration of the new plant reinforces the need for the world to closely monitor Iran's nuclear program.
The inauguration ceremony came a day after the US announced it would participate directly in group talks with Iran over its nuclear program, another significant shift from former US president George W. Bush's policy toward a nation he labeled part of an axis of evil.
Britain, China, France, Germany and Russia announced Wednesday they were inviting Iran to a new session of negotiations aimed at breaking a deadlock in the talks.
Iran has not yet replied to the invitation.
Following the US decision to be a full participant in talks with Iranian officials held by senior diplomats from the five permanent UN Security Council members plus Germany, a senior adviser to Ahmadinejad said Thursday that the Islamic republic would decide on a response to the overture after evaluating the details.
"We will review it and then decide about it," Ali Akbar Javanfekr told Reuters.
China urged the Islamic republic to pursue negotiations.
"We are glad to see an improvement in relations between the United States and Iran," Chinese Foreign Ministry spokeswoman Jiang Yu told a press conference in Beijing on Thursday. "We encourage Iran and other parties to have active contacts to seek an all-round, appropriate and long-term solution to the Iran nuclear issue."
