The Russian government is linking a brewing effort to revive the 2015 Iran nuclear deal with ongoing international sanctions against the Kremlin over its invasion of Ukraine — potentially casting the cautious talks into doubt.

Russian Foreign Minister Sergey Lavrov said the Russians want promises that the sanctions being imposed on Moscow for its invasion will not affect its trading relationship with the Iranian regime..

“We need guarantees these sanctions will in no way affect the trading, economic and investment relations contained in the (deal) for the Iranian nuclear program,” Lavrov said.

“We have asked for a written guarantee…that the current process triggered by the United States does not in any way damage our right to free and full trade, economic and investment cooperation and military-technical cooperation with the Islamic State,” he said according to The Wall Street Journal.

Talks have been ongoing in Vienna for weeks as part of the effort to bring the U.S. and Iran back into the 2015 Joint Comprehensive Plan of Action (JCPOA.) A European diplomat told Fox News on Friday that a new deal is expected within days,

However, the diplomat noted that any deal that involves countries like Iran, Russia, China and the U.S. could always unravel — while on Saturday a Western diplomat told the Journal that such a demand from Russia could throw the deal into doubt.

The JCPOA set limits on Iran’s nuclear activity in exchange for a significant rollback of international sanctions. The Trump administration pulled the U.S. out of the deal amid concerns that the agreement did not do enough to curb Iran’s nuclear ambitions — including the sunset clauses on restrictions.

Iran eventually pulled out of the deal after the Trump administration re-imposed sanctions as part of its maximum pressure campaign, and Tehran has been ramping up its enrichment since then.