Russian President Vladimir Putin on Tuesday told Iran's top nuclear negotiator that Tehran's nuclear program should be transparent and remain under control of the U.N. nuclear watchdog.

Foreign Minister Sergey Lavrov, meanwhile, said after talks at Putin's suburban residence that Saeed Jalili pledged that Iran would quickly answer all outstanding questions of the International Atomic Energy Agency.

The talks came one day after a new U.S. intelligence report that said Iran stopped work to develop nuclear weapons four years ago.

Russia has taken a careful stance on Iran, where it is building a $1 billion nuclear reactor, seeking to preserve economic and political ties with Tehran without angering the West. Moscow has urged Tehran to cooperate with international nuclear inspectors, but has said it sees no evidence that Iran is seeking to develop nuclear weapons, as the United States and its allies had contended.

"We welcome the extension of your cooperation with the IAEA. We expect that your programs in the nuclear sphere will be open, transparent and be conducted under control of the authoritative international organization," Putin said at the start of a meeting with Jalili at the presidential residence on Moscow's outskirts.

Neither Putin nor Jalili made reference to the U.S. National Intelligence Estimate on Iran, a synthesis of information from American spy agencies that concluded that Iran had suspended its attempt to build a nuclear weapon in 2003.

The assessment's unclassified summary, released Monday, was a surprising reversal of the previous U.S. intelligence view that Iran is aggressively pursuing a nuclear program for military purposes.

Iran praised the U.S. assessment Tuesday, with Foreign Minister Manouchehr Mottaki saying Tehran welcomed Washington's move to "correct" its view on the country's nuclear activity, which Iran has insisted is for peaceful purposes like power production.

Speaking to reporters after Putin concluded his meetings with Jalili, Lavrov said Iran promised to answer all outstanding questions of the IAEA.

Jalili "told us about their cooperation with the IAEA and elaborated on the plans of the IAEA and Iran to close all outstanding issues in the nearest time possible," he said.

"We are taking note of Tehran's determination to fully cooperate with the IAEA. We also appreciate Iran's adherence ... to the treaty on nonproliferation of nuclear weapons and observing all of its content," Lavrov said.

Russia is building Iran's first nuclear power plant in the port of Bushehr, but it has delayed the launching of the plant, saying Tehran has been slow to make payments. Iranian officials have denied payment delays and accused Moscow of kowtowing to the West.

During his trip to Iran in October, Putin promised that Russia would complete the Bushehr plant, but refused to say when it could begin operations. He said a decision on shipping fuel for Bushehr would be made once Russian and Iranian experts agree on revisions to the contract.

IAEA inspectors finished their inspection of the Siberian plant that is preparing the Bushehr fuel late last month and sealed the fuel containers.

Experts predict Putin is likely to use the construction of the plant as a bargaining chip in his efforts to persuade Tehran to show some cooperation with the West.

Russia and China, another important ally of Iran, have grudgingly approved two sets of limited United Nations sanctions against Iran over its refusal to suspend uranium enrichment. But the Kremlin has bristled at the U.S. push for tougher measures, saying they would only widen the rift.