After eleven months of talks, negotiators appear close to striking a deal to revive the 2015 Iran nuclear deal, which lifted sanctions on Tehran in exchange for curbs on its nuclear program.   

But the negotiations have been complicated by a last-minute demand from Russia for "written guarantees" from the United States that wide-ranging Western sanctions targeting Moscow over its invasion of Ukraine would not affect its economic and military cooperation with Iran.

The US has promptly rejected Russia's demand, with Secretary of State Antony Blinken saying that such demands are "irrelevant" and that sanctions on Russia over its Ukraine invasion "have nothing to do with the Iran nuclear deal."

Iran said it was seeking clarifications from the Russian side on what exactly their demands were. "We are still waiting for more details [from Moscow]," Foreign Ministry spokesman Saeed Khatibzadeh told the press Monday.

Meanwhile, Western powers warned Moscow on Tuesday against wrecking the almost completed deal on bringing the United States and Iran back into compliance with the accord.

"The window of opportunity is closing. We call on all sides to make the decisions necessary to close this deal now, and on Russia not to add extraneous conditions to its conclusion," Britain, France and Germany said in a joint statement to the UN nuclear watchdog's 35-nation board of governors.

Russia using JCPOA as a bargaining chip?

"Since the start of the Russian invasion of Ukraine, there have been concerns that the new developments, especially the growing confrontation between Russia and the West, might negatively impact the negotiations to revive the Iran nuclear deal," said Hamidreza Azizi, an expert on Iran affairs at the Berlin-based German Institute for International and Security Affairs (SWP).

"At the core of the concerns has been the argument that Moscow may try to take the JCPOA talks hostage to its benefits or use it as a bargaining chip to reach a deal with the West over Ukraine," he told DW.

"Russia is currently under unexpected and increasing international pressure over its Ukraine adventure. In the best-case scenario, Russia's request for guarantees from the US may be a political maneuver aimed at reminding the US and European states that they still need Moscow's cooperation to solve some issues of their urgent interest," the expert underlined.

"In this scenario, Moscow may just maneuver over the JCPOA for some time and delay a final agreement, but in the end, its own nonproliferation interests will bring it onboard to finalize the deal."

'Very complicated situation for Tehran'

Diplomats from Iran and world powers have been engaging in talks in Vienna for months to restore the 2015 nuclear deal. 

Moscow is a direct party — along with Britain, China, France and Germany — to the ongoing talks in Vienna. Washington is participating indirectly, as former president Donald Trump withdrew from the agreement in 2018.

Iran and the UN nuclear watchdog said Saturday they had agreed an approach for resolving issues crucial to reviving the accord.

The agreement, if fully implemented, would bring the United States and Iran back into compliance with the original deal, the Joint Comprehensive Plan of Action (JCPOA).

It will likely provide significant economic benefits to Iran, allowing the country to sell oil and gas freely and access the global financial system. In exchange, Tehran will restrict uranium enrichment as well as accept international inspections and other curbs on its nuclear program. 

The last-minute Russian demand, however, could complicate reaching an accord.

"I believe Tehran is in a very complicated situation right now. The Islamic Republic has for decades tried to depict Russia as an ally or at least a strategic partner, and it would come with a huge public backlash if they now admitted publicly that they've been played by the Russians," said SWP expert Azizi.

"At the same time, Tehran seems to want the deal now even more than before, as the increasing oil prices may make a huge contribution to the recovery of Iran's sanctions-hit economy."

'The only viable option for Iran'

Moscow's war against Ukraine and the resulting massive international sanctions have sent the Russian economy into a tailspin. It has also led to a sharp spike in the prices of commodities from oil and gas to wheat and nickel, among other things.

Iran could export more oil and benefit hugely from the surge in prices if the nuclear deal is restored. Exports of crude, the oil-rich nation's economic lifeline, have slumped as a result of the US sanctions. Estimates suggest that they dropped from about 2.8 million barrels per day in 2018 to as low as 700,000 barrels per day.

Energy expert Dalga Khatin Oglu believes that even if the sanctions are lifted, Iran will not be able to regain its place on the market immediately "because its main customers in Asia — for example, South Korea, Japan or India — have switched to importing from other countries."

"Six years ago, when the nuclear agreement was reached, it took Iran a few months to ramp up its export volume to the old level." 

After a phone call with his Russian counterpart Sergei Lavrov on Monday, Iranian Foreign Minister Hossein Amir-Abdollahian said, "We want to conclude a good agreement and we will not allow any foreign factor to influence Iran's national interests at the Vienna talks."

However, he did not reveal anything about the content of his conversation with Lavrov.

Azizi, the SWP expert, said that the more desperate the Russians become in Ukraine, the less likely it would be for them to accept Iran's request not to tie the JCPOA to the Ukraine crisis.

"The only viable option for Iran would be to enter into bilateral talks with the US — something Tehran has so far refused to do. At the end of the day, it's the US sanctions that Iran has been negotiating their removal," he pointed out, stressing: "Bilateral talks with Washington could, to a great extent, neutralize Moscow's sabotage acts at the current situation."

This article was originally written in German.

Edited by: Leah Carter