TEHRAN, Iran - Iran's top leader Ayatollah Ali Khamenei warned Wednesday the country will pursue nuclear activities outside international regulations if the UN Security Council insists it stop uranium enrichment.

The reactor building of Iran's nuclear power plant is seen, at Bushehr, Iran, 750 miles (1,245 kilometers) south of the capital Tehran, in this Sunday, Feb. 27, 2005, file photo. [AP]

"Until today, what we have done has been in accordance with international regulations," Khamenei said. "But if they take illegal actions, we too can take illegal actions and will do so."

Khamenei did not elaborate what "illegal actions" could be pursued by Tehran as it faces new sanctions by the UN body over its refusal to halt enrichment which the West fears is used for arms making.

Earlier Wednesday, Russia's foreign minister said it will not support "excessive" sanctions against its economic partner Iran, as the UN Security Council drew closer to a vote on a new, harsher set of measures intended to push Tehran to freeze its nuclear program.

Ambassadors from the 15 Security Council nations held informal discussions at Britain's UN Mission in New York ahead of a meeting later Wednesday to discuss possible changes to the draft resolution.

Germany and the five veto-wielding permanent council nations ¡ª the United States, Russia, China, Britain and France ¡ª agreed on the modest package of new sanctions Thursday to step up pressure on Iran to suspend uranium enrichment, which can be used to produce nuclear energy or nuclear weapons.

Russian Foreign Minister Sergey Lavrov said Moscow "will not support excessive sanctions against Iran," and added that the draft resolution has been softened at Moscow's behest.

Lavrov also denied claims that Moscow had told Iran it would not deliver nuclear fuel for the Russian-built Bushehr nuclear power plant in southern Iran unless Tehran complies with UN demands.

"There is no link whatsoever between the UN resolution ... and the implementation of the Bushehr project," he told lawmakers in the lower parliament house.

The proposed new sanctions in the draft resolution would ban Iranian arms exports and freeze the assets of 28 additional individuals and organizations involved in the country's nuclear and missile programs ¡ª about a third linked to Iran's Revolutionary Guard, an elite military corps.

The package also calls for voluntary restrictions on travel by the individuals subject to sanctions, on arms sales to Iran, and on new financial assistance or loans to the Iranian government.

Lavrov said an earlier, tougher version of the draft resolution that included broader restrictions on officials' travel and a ban on credits to Iran had been softened on Russia's advice. "We ... have agreed to influence Iran by gradually applying proportionate pressure," Lavrov said.

At Russia's insistence, neither the existing Security Council resolution nor the draft being discussed makes any mention of Bushehr. Lavrov said the Bushehr contract is in line with all international agreements aimed at preventing nuclear weapons proliferation.

European and U.S. officials who spoke on condition of anonymity because of the sensitivity of the talks said Tuesday that Moscow had bluntly told Tehran it would not ship fuel for Bushehr until Tehran freezes its uranium enrichment program, as demanded by the UN Security Council.

Lavrov dismissed the claims as an "unscrupulous trick."

"It's not the first time that we are seeing such an unscrupulous approach aimed at driving a wedge between us and Iran," he said.

Russia has said fuel for Bushehr would not be supplied this month, as had been planned earlier, because of alleged Iranian payment delays that prompted Moscow to indefinitely postpone the Bushehr reactor's launch, which had been set for September. Russian officials also said that the number of workers at Bushehr had dwindled due to the funding shortage.

Iran angrily denied falling behind in payments and accused Russia of caving in to U.S. pressure to take a tougher line on Tehran. Iranian state television on Tuesday described Russia as an "unreliable partner," adding: "It is clear that Russia has stopped construction of this plant under pressure and for political reasons."

On Wednesday, Lavrov repeated Russia's assertions that Iran had dragged its feet on payments for Bushehr.

"Regrettably, our Iranian colleagues aren't telling the truth when they blame Russia for the financial problems which have emerged. Financial problems do exist, but they are linked to the Iranian side breaching an earlier-agreed schedule of payments," he said.