Russia on Friday asked for a major revision of the UN Security Council draft resolution that seeks sanctions against Iran for its nuclear ambitions, diplomatic sources said.

Russian UN envoy Vitaly Churkin, fresh from Moscow with instructions on how to amend the draft, said Russia believed the resolution should not drive Iran away from negotiations, and should exclude mention of the Busher nuclear plant that Russia is building in the southwest of Iran.

"We believe that first of all the resolution which the Security Council will be considering should facilitate the continuation of our talks with the Iranians," he said.

His U.S. counterpart John Bolton said because Russia presented a complete line-in, lineout version of edits, the draft's sponsors would circulate their own text later on Friday afternoon.

Bolton said all the text would be sent to governments, and the ambassadors of the five permanent members of the Security Council would meet some time next week.

Russian Foreign Minister Sergei Lavrov has said time and again this week that the resolution was too harsh on Iran's nuclear program.

He said sanction measures had to be "reasonable" and "proportional" and warned that the European draft went too far.

Lavrov has also said that the resolution should focus only on areas the UN nuclear watchdog, the International Atomic Energy Agency (IAEA), has defined as serious concerns, such as uranium enrichment, chemical processing, and heavy water reactors.

His views were shared by the Chinese UN ambassador Wang Guangya who expressed caution that the resolution would corner the Iranians. Wang said sanctions should be imposed in stages and be used to put "political pressure on the Iranians to come back to negotiations."

The draft resolution, sponsored by Britain, France and Germany, mandated nuclear and ballistic-missile-related trade sanctions. It also called for a freeze on assets related to Iran's nuclear and missile programs, and travel bans on scientists involved in those programs.

The draft was in response to an earlier Security Council resolution demanding Tehran suspend its uranium-enrichment activities by Aug. 31.