World powers resumed crisis talks with Iran Sunday in hopes that a crippling oil embargo will finally force Iran to scale back its nuclear drive.

The two-day meeting follows a bruising May session in Baghdad during which Iran nearly walked out of negotiations aimed ultimately at keeping it from joining the exclusive club of nations with an atomic bomb.

Host Russia however is keen to flex its diplomatic muscle and make Iran an example of how Moscow's influence over its partners could be used to avoid foreign military intervention in the 16-month crisis raging in Syria.

"There are reasons to believe that the next step will be taken in Moscow," Russia's Deputy Foreign Minister Sergei Ryabkov said Friday. "It is important for Russia to ensure that the negotiating process continues."

Failure in Moscow could leave the process in tatters and raise the threat of air raids from Israel, a fateful scenario in which broader conflict would lead to a spike in oil prices that could tip over the world's teetering economy.

But a July 1 deadline for a full EU oil embargo and the June 28 rollout of US sanctions against a host of Iranian oil clients is providing added incentive for Tehran to bargain more seriously.

Two of the biggest bones of contention involve the speed with which world powers lift existing sanctions and the recognition of Iran's "right to enrich."

Iranian President Mahmoud Ahmadinejad told a German Sunday paper that his country was ready to take a "positive step if the other party makes a similar step" at the talks.

During an interview with the Frankfurter Allgemeine Sonntagszeitung, Ahmadinejad also said he will end his political career when his second term ends next year, according to The Associated Press.

Ahmadinejad can't run in Iran's June 2013 elections because of term limits. Asked whether he envisions returning to the presidency at a later date, he replied, "No, eight years are enough."

He said that, though he might engage in political activity at a university, "I will not found any political party or group," the AP reported.

EU officials say Iran has agreed to discuss the idea of limits to its enrichment program under a proposal initially outlined in Baghdad.

The deal would see Iran stop enriching uranium to 20 percent, seen as being just steps away from weapons-grade, and ship out its existing stock while also shuttering its forbidden Fordo bunker.

AFP