Russia demands on sanctions cause pause in Iran nuclear talks in Vienna

March 11 (UPI) -- Talks in Vienna aimed at a revived nuclear deal with Iran were paused indefinitely on Friday after Russia demanded that sanctions related to its invasion of Ukraine do not prohibit trade between Moscow and Tehran.

Josep Borrell, the European negotiator for the talks, said in a tweet that he would speak to representatives from the United States, Iran and other nations "to overcome the current situation and to close the agreement."

"It's certainly serious. If you lose momentum at this late stage the dynamics shift in ways that it could become impossible to resume the talks," said Esfandyar Batmanghelidj of the European Council on Foreign Relations, according to a report in The Washington Post.

Following weeks of negotiations in Vienna between the United States, Iran, Russia, China, Britain, France and Germany, there is now concern among experts that prospects for a deal could fail.

Henry Rome, deputy head of research at Eurasia Group, told CBS News on Wednesday that Russia is throwing "a last minute wrench into the negotiations."

"The negotiators by all accounts were within days of locking down the revival of this agreement when the Russians came out over the weekend throwing some new demands on the table, such that if U.S. sanctions on Iran are lifted through the agreement, the Russians want to insure that they are also able to benefit from that as well. And of course they are under a series of crippling Western sanctions for their invasion of Ukraine," Rome said.

According to a report in Foreign Policy, Russia has now reversed its policy of keeping the Iran talks separate from its pressure on and invasion of Ukraine.

Foreign Policy notes that Mikhail Ulyanov, Russia's chief negotiator at the talks, said in late December: "We are pragmatic. In support of the Vienna talks, we never discuss Ukraine."

Meanwhile, Israeli Prime Minister Naftali Bennett in February told an umbrella group of American Jewish organizations that the current version of the Iran nuclear deal being negotiated will not curb violence in the Middle East.

President Joe Biden, who was vice president when then-President Barack Obama participated in the July 2015 accord with Iran, which included other world powers, restarted the Iran nuclear talks upon his election in 2021.

That was in response to an action taken by former President Donald Trump to withdraw the U.S. from the deal.