Russian Deputy Foreign Minister Sergei Ryabkov denied Friday that a sanctioned Iranian military commander had secretly visited Moscow recently, a development that would embolden opposition to the Iran nuclear deal in Congress.

In a briefing with journalists in Moscow, Ryabkov said that reports of the visit by Iranian Maj. Gen. Qasem Soleimani to Russia had evoked “great surprise.” Secretary of State John F. Kerry confronted Russian Minister Sergei Lavrov over the reported visit during a telephone call Thursday.

“We informed our American colleagues that we don’t have this information, that Soleimani was not in Moscow,” Ryabkov told journalists in remarks confirmed by a Foreign Ministry spokeswoman. “We thought this question was closed.”

Soleimani — the head of Iran’s Quds Force, an elite special operations unit of the Revolutionary Guard Corps — oversees Iranian support for militias opposed to the Islamic State in Iraq, military assistance to Syrian President Bashar al-Assad, and Iran’s support for Hezbollah and Hamas.

He is also accused of arming Shiite militias responsible for the deaths of U.S. troops during the Iraq war and has been sanctioned by the State Department for abetting terrorism. In a recent hearing of the Senate Armed Services Committee, Kerry said that U.S. sanctions against Soleimani would “never” be lifted.

Iranian Maj. Gen. Qasem Soleimani leads the Quds Force, an elite unit of the Revolutionary Guard Corps. (Office of the Iranian Supreme Leader via AP)

Soleimani’s alleged visit to Russia was seized on by critics in the United States as proof of Moscow’s lack of commitment to the Iran deal. Under the deal, a U.N. travel prohibition against Soleimani would be lifted eight years after the accord was implemented.

Ryabkov said Friday that Russia is fully committed to holding up its end of the bargain and accused critics in the United States of using “only political arguments and none based on substance.”

He said that he expects the accord to be signed into law by President Obama, despite some opposition in the Senate, and that Russia has not made contingency plans in case the deal falls through. Congress is expected to vote on a resolution of disapproval in September, but it is unclear whether — even if the measure passed — opponents of the deal would be able to gather enough votes to override a veto by the president.

The rollback of sanctions will offer Russia the chance to expand trade with Iran, including the sale of arms. President Vladimir Putin in April announced that Russia would lift a self-imposed ban on delivering advanced S-300 antiaircraft missiles to Iran following progress in the talks.

On Friday, Ryabkov defended the potential delivery of the weapons system, saying the matter is a “strictly bilateral topic” that does not concern other countries.

He also said Russia and Iran have reached a preliminary agreement for Iran to ship its excess low-level enriched uranium to Russia, which would supply natural uranium in exchange.

Ryabkov, speaking to journalists and members of Russia’s expert community, defended the accord against hawkish criticism that Moscow should have scuttled the deal. In particular, he addressed concerns that Iran’s expected return to the oil market had lowered oil prices, cutting Russian energy revenue in the process.

“Would there have been a deal if Russia had not participated in these talks?” Ryabkov asked rhetorically. “I think there would have been a deal, but the conditions would have been far worse for the Russian Federation.”

Ryabkov also reiterated demands that the United States abandon a planned missile defense shield in Europe, citing a 2009 speech in which Obama said it was needed to protect against an Iranian military threat.

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