ROME — Silvio Berlusconi, the former Italian prime minister, campaigned to be the protector of democratic, pro-European values in a new right-wing coalition that is expected to take power in days after winning elections last month.

But even before a government can be sworn in, the 86-year-old billionaire media mogul has proved himself to be less of a stable, moderating force, than the source of renewed anxiety after the leak of surreptitiously recorded remarks revealed that he blamed Ukraine’s president, Volodymyr Zelensky, for forcing President Vladimir V. Putin of Russia to invade Ukraine.

The remarks, complete with talk about a “sweet letter” and vodka from Mr. Putin, raise concerns that the new right-wing government, led by Giorgia Meloni, herself a solid supporter of Ukraine, is wobblier than expected and could, if it ever actually comes together with another Putin-admiring partner, potentially lead Italy to undercut Europe’s united front against Russia.

“I reconnected a little bit with President Putin,” Mr. Berlusconi could be heard saying on the audio published on the website of La Presse on Tuesday, in which he addresses a meeting of loyal Forza Italia party members, and some apparently not-so-loyal leakers. In the audio, he added that Mr. Putin had sent him 20 bottles of vodka “and a very kind letter” for his 86th birthday last month. Mr. Berlusconi said he responded by sending bottles of Lambrusco wine and “an equally sweet letter.”

Mr. Berlusconi has not disputed the authenticity of the remarks. On Wednesday, a European Commission spokeswoman said it was investigating whether the vodka shipment constituted a violation of European sanctions against Russia.

But it was additional remarks leaked on Wednesday that did the most damage.

“Do you know how the Russia affair came about? On this too, however, I beg you to please keep this in the strictest confidence. Promise?” Mr. Berlusconi can be heard saying on the tape. He then blamed Ukraine for violating the Minsk agreement over the Donbas territories, killing “I am told 5, 6, 7 thousand” people in the territories, leading to an appeal to Mr. Putin for protection.

“They say, ‘Vladimir, we don’t know what to do. Defend us.’ He is against any initiative, he resists, he is under heavy pressure from the entire Russia. So he decides to invent a special operation: the troops were supposed to enter Ukraine, reach Kyiv in a week, depose the incumbent government, Zelensky and so on, and install a government already chosen by the Ukrainian minority” composed of more sensible leaders, “and then leave the following week.”

Instead, in Mr. Berlusconi’s telling, Mr. Putin was caught off guard by a resistance fueled by weapons “from the West.” He added, “Zelensky in my opinion — never mind I can’t say anything,” at which point he was interrupted by cheers from his supporters. “Today unfortunately in the Western world there are no leaders, there are no leaders in Europe and in the United States of America. I don’t tell things. I know that there are no real leaders. Can I make you smile? The only real leader is me.”

Those remarks echoed a previous bout of Putin apologetics by Mr. Berlusconi last month on one of the country’s most prominent political talk shows. At the time, he said his words had been taken out of context. But the fact that he said the same thing in private and appeared to be doubling down on the side of Mr. Putin drew widespread condemnation from across the political spectrum.

On Thursday, Mr. Berlusconi went into damage-control mode. On Twitter, he called it “ridiculous” that Italy’s center-left opposition, which ran with leftist parties critical of NATO, can “permit themselves to criticize me.” In another post, he said it was “simply ridiculous” to question his pro-NATO position.

Within days, the hard-right leader Giorgia Meloni, who emerged victorious from elections last month, is expected to become prime minister. But she needs Mr. Berlusconi’s support, and he has now become the largest, and most erratic, obstacle to forming a government.

Last week, as he demanded key ministries for his loyalists, he insulted Ms. Meloni’s boyfriend by referring to him as merely an employee of a television channel Mr. Berlusconi owned. Photographers captured an image of Mr. Berlusconi’s notes with an actual list of insults about Ms. Meloni’s personality. (“Overbearing, arrogant, offensive.”)

But condemnation of Mr. Putin is critical to her credibility as a pro-Western ally, and helps allay concerns resulting from her origins in post-fascist politics, her past anti-European Union vitriol and her closeness to illiberal leaders such as Prime Minister Viktor Orban of Hungary. A member of Mr. Berlusconi’s party seemed poised to serve as a reassuring foreign minister. It’s not clear that can happen now.

Prime Minister Mario Draghi, the departing prime minister and an architect of Europe’s united front against Russia, worked hard to shift Italy away from its dependence on Russian gas and generally pro-Russian view, both of which Mr. Berlusconi helped foster during his many years in power as a four-time prime minister.

Italy’s left has a lingering affinity for Russia from its days as the largest Communist Party in Western Europe. But Mr. Berlusconi helped bring the right close to Russia.

During Mr. Berlusconi’s time in power, he grew fond of Mr. Putin. Mr. Berlusconi named a bed after Mr. Putin, gave Mr. Putin bedsheets featuring the two leaders shaking hands, and hosted Mr. Putin’s then-young daughters at his Sardinian villa.

Recently, he said he was disappointed in his old friend, a distancing seen as necessary to position himself as a centrist counterbalance to Ms. Meloni’s other coalition partner, Matteo Salvini, the leader of the League party, on the issue of Russia. Mr. Salvini used to wear T-shirts with Mr. Putin’s face on them, made a populist career out of opposing sanctions on Russia and once even said he preferred Mr. Putin to his own president.

After Mr. Berlusconi’s remarks, Ms. Meloni, who vowed in a recent interview to keep sending Ukraine arms, seems increasingly alone in her support of Ukraine. There is also increasingly political pressure from the left.

Former Prime Minister Giuseppe Conte condemned Mr. Berlusconi’s remarks, but this week he announced he would take part in a large demonstration on Nov. 5 demanding peace for Ukraine and an end to arms shipments. He called incessantly for an end to the shipments on the campaign trail as he recast himself as a populist hero of the poor in Italy’s south, who he said should be the recipients of the money instead spent on weapons.

Critics say Mr. Conte is advocating Ukraine’s surrender, but he seems to have more and more allies. The Vatican and Italian Roman Catholic Church, which are politically powerful in Italy, have seemed to drift toward the peace-at-all-costs column.

This week, Cardinal Matteo Zuppi, the president of the Italian church and a close ally of Pope Francis, who has himself been reluctant at times to call out Mr. Putin, was quoted by the Italian news agency ANSA saying that it was “better to lose a piece of sovereignty and resolve conflicts. Instead of taking up arms, let’s talk about it.”