Iran announced Wednesday that it would stop complying with certain elements of the Joint Comprehensive Plan of Action, better known as the Iran nuclear deal, in 60 days if the remaining signatories did not find a way to make the deal more economically beneficial to Iran.

One of those remaining signatories met the news with a very different reaction than the others.

The announcement came a year after President Trump withdrew the United States from the deal — and subsequently reimposed sanctions that made it difficult for Iran to reap the benefits of remaining in the deal. The deal’s European signatories, France, Germany and Britain, which had tried to persuade the Trump administration to keep the United States in the deal, are now caught between their ally, the United States, and the deal they very much want to keep alive.

“We urge the Iranians to think very long and hard before they break that deal,” Jeremy Hunt, British foreign secretary, said Wednesday, referring to Iran’s threat to hold onto excess uranium and heavy water stockpiles. “Today, nothing would be worse than Iran, itself, leaving this accord,” French Defense Minister Florence Parly told France’s BFMTV.

But Russia’s foreign minister, Sergei Lavrov, appearing in Moscow with Mohammad Javad Zarif, his Iranian counterpart, said, “The U.S. is to blame for the situation and it makes it difficult for both Iran to fulfill its obligations and … for the general state of the nuclear nonproliferation regime.”

It isn’t that Russia is particularly pleased about the latest developments — “Russia does not particularly want to see the agreement fall apart, not least because it has a stake in the diplomatic achievement of which it was part,” Matthew Rojansky, director of the Wilson Center’s Kennan Institute, wrote in an email — but rather that, of all parties involved, Russia has benefited the most from the sequence of events that began a year ago, when Trump announced that the United States was leaving the deal.

For one thing, the United States leaving the deal gave Russia the opportunity “to have its cake and eat it, too,” Rojansky wrote. “Moscow was a pivotal player in negotiating the original agreement, for which it enjoyed quite a lot of credit. . . . Now that the U.S. has pulled out, Moscow can blame Washington for its impending failure, part of its broader critical narrative about the U.S. in the Middle East and globally.”

For another, the fact that the world can’t buy Iranian oil without risking the wrath of the United States has helped Russia. “The price of oil is 30 percent higher than a year ago,” said Barbara Slavin, director of the Atlantic Council’s Future of Iran Initiative, a reality that is at least in part a result of “what the Trump administration has done on Iran.”

“The Russians can just sit back and enjoy the higher oil prices,” she said.

The Russians are enjoying, or at least benefiting from, another side effect of U.S. pressure on Iran, too: a close relationship with Iran.

“Iran has become an important partner for Moscow, especially given their shared interest in undermining U.S. influence in the Middle East. Russia-Iran relations are stronger than they have been historically,” wrote Andrea-Kendall Taylor, director of the Transatlantic Security Program at the Center for a New American Security, in an email to The Washington Post. “Their repeated interactions through Moscow’s support for Iran in implementing the JCPOA and operations in close proximity on the battlefield in Syria have overcome historic mistrust and build a foundation for cooperation.”

Zarif, in Moscow, contrasted the support he said Iran had received from Russia and China with that demonstrated by the nuclear deal’s European signatories.

“Our friends in Russia and China maintained very good relations with us in this year” since Washington quit the agreement,” Zarif said. “But the rest of the JCPOA participants did not meet any of their obligations.”

After Iran’s ultimatum Wednesday, “as other states are forced to choose between the tougher U.S. position and staying engaged with Iran, Russia will be well positioned to expand on already strong political, security and trade ties with the Islamic Republic,” Rojansky wrote.

That doesn’t mean Russia wants the deal to disintegrate (it doesn’t) or that Russia’s alliance with Iran doesn’t bring with it other headaches. (It does: As Kendall-Taylor, former deputy national Intelligence officer for Russia and Eurasia at the National Intelligence Council, wrote, “Russia will want to preserve its relations with Tehran, but it will not want to be seen as firmly standing in Iran’s corner because doing so could alienate countries like Saudi Arabia where the Kremlin has worked to increase ties.")

What it does mean is that Russia has received economic and geopolitical benefits from what has, for many others, been purely negative. Lavrov’s appearance Wednesday with Zarif only underscored that.

“They don’t look isolated,” Slavin said. “The United States looks isolated.”