President Vladimir V. Putin of Russia received the geopolitical equivalent of manna from heaven on Friday when British voters opted to leave the European Union, speeding his long-term goal of weakening the most powerful alliance confronting the Kremlin as it seeks to rebuild its superpower muscles.
Officially, Moscow presented a sober facade, echoing the prevote stance by Mr. Putin and other senior officials that the British referendum was not their concern and would have no direct consequences on Russia.
From other precincts, however, came eruptions of undisguised glee.
“We must express solidarity with the British people, with their right decision to exit the European Union,” Vladimir V. Zhirinovsky, the populist politician whose statements often reflect the national mood, said in a speech in Parliament. “They did a great deed!”
One commentator on Facebook suggested that Britain should be renamed the “Londonskaya Narodnaya Respublika, or London People’s Republic. That echoed the names of the two breakaway regions of southeastern Ukraine that Russia has supported militarily in their fight against the central government in Kiev.
The Russian government, which has worked assiduously to undermine European solidarity in recent years, has any number of reasons to celebrate, analysts said.
“The Kremlin is interested in any kind of disagreement, any kind of trouble in the E.U. which makes it weaker,” said Nikolay V. Petrov, a professor of political science at the National Research University’s Higher School of Economics in Moscow.
For starters, he noted, the vote removes Britain as an influential voice in European efforts to isolate and punish Russia over its annexation of Crimea and role in destabilizing Ukraine. Second, it helps Mr. Putin in his preferred method of dealing with strong countries on a one-to-one basis rather than as blocs. Third, it can be exploited at home as an example of how a lack of unity can lead to weakness.
“It can be used domestically to demonstrate that we are strong and everybody around us is not that strong,” Mr. Petrov said. As for any negative economic consequences, he added, “Those are not the highest priority — geopolitically and strategically the Kremlin thinks it will benefit.”
While France and Germany, not Britain, led the drive to impose sanctions on Russia for the annexation of Crimea and the Ukraine crisis, there was some hope that those issues would fade somewhat now that Europe confronts monumental internal problems.
“I don’t think the European Union will now have time to think about Ukraine or about sanctions,” said Andrei Klimov, the deputy chairman of the international affairs committee of the upper house of Parliament.
An unidentified Foreign Ministry spokesman told Interfax that Russia expected Britain’s hard-line stance against sanctions to continue unchanged, although some analysts said they expected that Europe without the British voice might not be so adamant.
“Without Britain, there won’t be anybody in the E.U. to defend sanctions against us so zealously,” Sergei S. Sobyanin, the mayor of Moscow, wrote on Twitter.
Mr. Putin has been trying to build close relations with countries that have been less adamant about keeping sanctions in place, among them Italy, France, Greece and Hungary. Russia has given open financial support to the far-right National Front party in France, whose leader, Marie Le Pen, called for a similar referendum on membership in the bloc after the British vote.
The Kremlin is also believed to be following the Soviet tradition of underwriting other political groups who seek to weaken the European Union. Many Russian officials and commentators said they expected similar referendums to be held across the Continent.
“Don’t be surprised if, instead of terms for individual countries like ‘Grexit’ or ‘Brexit,’ there will soon be a universal one, ‘Whoexit,’ ” Maria Zakharova, a Foreign Ministry spokeswoman, wrote on her Facebook page.
Mr. Putin broke his silence about the British campaign last week to deny accusations that the Kremlin was trying to sway the outcome.
“It is unpleasant to link Russia to every problem, even those with which we have no link, nor to make Russia into a kind of boogeyman,” he said. “I should say that this is absolutely none of our business. This is the choice of the British people.”
The Russian leader is not a fan of unpredictable votes, and he expressed puzzlement about why the British prime minister, David Cameron, decided to hold the referendum in the first place.
“Why did he initiate this referendum, why did he do it?” Mr. Putin asked. “To intimidate Europe, or to threaten someone? What is the point of this if he himself opposes the idea?”
On Friday, Mr. Putin’s spokesman, Dmitry S. Peskov, told Russian news outlets that he hoped that a Britain outside the European Union would understand “the need to build good relations” with Russia.
Despite Russia officially not taking a position on the British vote, state-run news reports by the English-language service of RT television and the Sputnik news agency openly supported a British exit from the bloc.
State-run news outlets give significant attention to issues that are considered central to the euroskeptic movement, particularly the migrant crisis, and they paint Europe as a continent in crisis. An analysis by Ben Nimmo, a senior fellow at the Britain-based Institute for Statecraft, of Sputnik’s English-language coverage found a significant bias toward the exit campaign.
“Across the spectrum of analytical pieces, commentaries and blogs, Sputnik’s writers used consistently anti-E.U. and anti-‘Remain’ language,” the report said.
After the vote, Margarita S. Simonyan, the editor in chief of both RT and Rossiya Segodnya, Sputnik’s parent company, joined in rejoicing. “Fun times begin,” she posted on Twitter, “#Where is my popcorn.”
Perhaps the only thing tempering the general euphoria were a few sobering notes on the economic impact.
Aleksei Makarkin of the Center for Political Technologies said that Russia would feel the economic effects of Britain’s vote. “While this is a political victory, on the economic side of things, Russia will suffer,” he said in an interview. “Oil will fall, the markets will be turbulent. Russia won emotionally, but lost economically.”
Mr. Makarkin said many Russians saw in the vote the possibility that the European Union might crumble, much the way the Soviet Union fell apart 25 years ago.
“The overall mood in Russia can be described as malicious joy,” he said. “A few liberals regret that Britain voted to leave, but in general there is some sort of relief that they have their problems too, they are collapsing, too.”