Russian President Vladimir Putin made an unspecified proposal about Iran's nuclear program at a private meeting with the country's supreme leader during a brief trip to Tehran, Iran's state news agency said Wednesday.

Russian officials could not immediately be reached to verify the report and the Iranian news agency provided no details on what Putin had proposed.

Ayatollah Ali Khamenei, who has the final say on all government matters, said Iran will give Putin's proposal serious thought before giving a response, the news agency said.

"We will ponder your words and proposal," IRNA quoted Khamenei as saying.

Officials close to hard-liners within Iran's ruling Islamic establishment said they believed the proposal by Putin was a type of "time out" on U.N. sanctions against Iran, if Tehran suspends uranium enrichment. The two officials spoke on condition of anonymity because of the sensitive nature of the issue.

"The main reason for Putin's visit to Iran was to convey this message personally to the ultimate power in Iran," one official said.

Khamenei told Putin that Iran is serious about continuing uranium enrichment in turn but wants to avoid adventurism and cooperate with the U.N. nuclear watchdog, the news agency said.

The five permanent U.N. Security Council members, plus Germany, have been working together to try to find a way to get Iran to abandon its uranium enrichment program. The U.S. and some allies allege that the program is cover for a weapons program. Iran says it is intended purely for peaceful energy production.

Putin met with Iranian President Mahmoud Ahmadinejad and attended a summit of Caspian Sea nations Tuesday, the first visit by a Kremlin leader to Iran since Josef Stalin attended a 1943 summit with Winston Churchill and Franklin D. Roosevelt.

Before visiting Iran, Putin held extensive talks on Iran's nuclear activities with some Western leaders including French President Nicolas Sarkozy and German Chancellor Angela Merkel.

Putin has bluntly spelled out his disagreements with Washington, saying last week that he saw no "objective data" to prove Western claims that Iran is seeking nuclear weapons.

At talks Friday with U.S. Secretary of State Condoleezza Rice and U.S. Defense Secretary Robert Gates, he ridiculed U.S. plans for a missile defense system in eastern Europe, supposedly to stop an Iranian attack.

On Tuesday in Tehran, Putin warned the United States not to use a former Soviet republic to stage an attack on Iran.

In June 2006 the Security Council permanent members group, offered a package of economic and political rewards to Iran and a suspension of the implementation of sanctions, but only if Tehran agreed to suspend enrichment before the start of negotiations. Iran rejected that proposal.

The Security Council imposed sanctions on Iran in December for refusing to suspend enrichment, and modestly increased them in March after Tehran stepped up the program. Iran responded by giving the U.N. nuclear watchdog less access to its nuclear facilities.

IRNA, the official news agency, reported Wednesday that Khamenei had told Putin that U.S. demands had no limits but that Iran won't seek adventurism.

"Iran ... has chosen a lasting logic in defending its national interests because it is certain that excessive demands of the enemies of this nation has no limits.

"Due to this reason, the Iranian nation and government, while avoiding adventurism and not giving pretexts to the enemy, will pursue this wise logic," IRNA quoted Khamenei as telling Putin.

Khamenei also said Iran will continue cooperation with the U.N. nuclear watchdog, the International Atomic Energy Agency, which is scrutinizing Iran's nuclear program.

"Iran's cooperation with the IAEA is a logical and correct path and will continue. We are determined to meet our country's need for nuclear energy. That's why we are taking the issue of enrichment seriously," IRNA quoted Khamenei as saying.

Khamenei said an "independent Iran" was in the interest of Russia, while a "powerful Russia" served the interests of Iran.

Russia has resisted the U.S. push for stronger sanctions against Tehran and strongly warned Washington against using force against Iran.

But its position is carefully hedged: It has delayed completing the Bushehr nuclear power plant, Iran's first, and is urging the country to comply with international controls on its nuclear activities.

Putin refused to set a date Tuesday for the startup of Iran's first nuclear power plant, but stressed that Moscow would not back out of its commitment to complete the project.

Setting a date by Putin to quickly complete the power plant could embolden Iran and further cloud Russia's relations with the West.