Updated

Iran told the U.N. nuclear watchdog agency Tuesday it planned to resume nuclear fuel research after a 2 1/2-year hiatus, a vague declaration that was likely to be taken in the West as fresh evidence Tehran was trying to build an atomic weapon.

International Atomic Energy Agency head Mohamed Elbaradei said it was important that Tehran "maintains its suspension of all enrichment-related activity" as a way of reducing international suspicions about its nuclear plans.

Mohammad Saeedi, deputy head of the Atomic Energy Organization of Iran, said research would "resume in cooperation and coordination with the IAEA in the next few days," adding that it would "have little to do with the production of nuclear fuel."

Beyond that, he would not specify what type of research Tehran planned but claimed its nuclear program had suffered significantly during the research suspension. He said Iran could no longer keep its research scientists in limbo.

Iran has said it remains determined, at some point, to resume uranium enrichment, a process that can produce fuel for nuclear weapons.

The Tuesday announcement, while vague, was certain to raise further concerns in the United States and among its European allies who believe Iran wants to build a nuclear arsenal. Tehran says its nuclear program is for electricity generation.

ElBaradei also called on Iran to "build confidence and enable the resumption of dialogue with all concerned parties."

The Iranian mission to the IAEA said Tehran has decided to resume from Feb. 9 research and development "on the peaceful nuclear energy program which has been suspended," Elbaradei told the agency's board.

A European diplomat accredited to the agency said it was too early to evaluate the significance of the move and whether it would scuttle talks planned for later this month.

The EU has previously said that any decision by Iran to resume work on its uranium enrichment program would be "the red line" that would end European attempts to negotiate differences with Iran.

Furthermore, the EU has said a resumption of work on the program would revive attempts to take Iran to the U.N. Security Council for violating the nuclear nonproliferation treaty.

But the diplomat, who demanded anonymity because he was not authorized to publicly discuss European Union strategy, said the Europeans needed details of precisely what Iran planned to research before making a decision on future talks.

Iran has come under heavy international pressure from the IAEA and the West to abandon its program to produce fuel for its Russian-built nuclear reactor that is due to come online this year and for its future nuclear power plants.

Iran has vowed it will never give up the right to produce nuclear fuel, which it says is guaranteed by the Nuclear Nonproliferation Treaty.

While refusing to permanently renounce uranium enrichment, Iran suspended many aspects of its nuclear fuel program in 2003 as a goodwill gesture during negotiations with the big three European powers, Britain, France and Germany.

The talks collapsed in August after Iran resumed uranium reprocessing activities, a step before enrichment, at its Uranium Conversion Facility in Isfahan, central Iran.

While the two sides resumed dialogue last month, talks have so far failed to resolve the dispute. More talks are scheduled for later this month.

Iran's decision to resume nuclear research coincided with the announcement by Asefi that Iran would reject a U.S. and European-backed Russian proposal to end the dispute if it required Tehran to cede the right to enrich uranium at home.

"The Russian proposal is ambiguous. We have to talk to the Russians to see what are the details," Asefi told reporters.

"If it means enrichment be carried out (only) in Russia, we have said it is not acceptable. But if it is a complementary plan, we will study it," Asefi said.

Extremists within the increasingly hard-line Iranian government have denounced the Russian proposal as a "dirty trick."