Vladimir Putin has lost interest in diplomatic efforts to end his war with Ukraine and instead appears set on seizing as much Ukrainian territory as possible, according to three people briefed on conversations with the Russian president.

Putin, who was seriously considering a peace deal with Ukraine after Russia suffered battlefield setbacks last month, has told people involved in trying to end the conflict that he sees no prospects for a settlement.

“Putin sincerely believes in the nonsense he hears on [Russian] television and he wants to win big,” said a person briefed on the talks.

Though Moscow and Kyiv agreed their first draft communique at a meeting in Istanbul in late March, talks stalled after Ukrainian president Volodymyr Zelensky accused Russia of committing war crimes against civilians in cities such as Bucha and Mariupol.

Putin said peace efforts were at a “dead end” and was infuriated after Ukraine sank the Moskva, the flagship of Russia’s Black Sea fleet, according to two of the people.

“There was hope for a deal. Putin was going back and forth. He needs to find a way to come out of this a winner,” one of the people said.

After the Moskva sank, “Putin was against signing anything. [ . . . ] after the Moskva he doesn’t look like a winner, because it was humiliating,” the person added.

Ukrainian and western officials had always doubted his commitment to peace talks, suspecting it was a way of buying time for Moscow’s offensive.

The Russian president appears to hold a distorted view of the war as set out by his generals and depicted on Russian television, the people briefed on conversations with him said.

They added that he insisted, despite all evidence to the contrary, that his forces have not targeted civilians during attacks such as the siege of the Azovstal steelworks, Ukrainian forces’ last holdout in the largely destroyed city of Mariupol.

Intermediaries such as Turkey’s president Recep Tayyip Erdogan, European Council president Charles Michel and billionaire Chelsea FC owner Roman Abramovich have been trying to convince Putin to meet Zelensky in hope they can break the deadlock.

Russian and Ukrainian negotiators have placed most other issues on the back burner while trying to thrash out a deal on guarantees for Kyiv’s security if it declares neutrality and abandons its drive to join Nato.

But Putin told Michel in a call on Friday that the talks had run aground because Ukraine “put up a wall” and said it “was not the right time” to meet Zelensky, according to a person briefed on that conversation.

Negotiators interpreted that as meaning Russia believes it can capture more territory, rather than being an indication that the talks need more time to find areas of agreement.

Putin is avoiding the meeting with Zelensky “with all his might,” a person involved in the peace talks said. “He wants everything to be decided before their personal meeting,”

Zelensky said on Saturday that he wanted the talks to go on but said Ukraine would not continue negotiating if people in Mariupol were killed, or if Russian authorities in the occupied southern region of Kherson were to stage a separatist referendum.

Officials in Kyiv are concerned Putin may go further than Russia’s stated goal of capturing the eastern Donbas border region and instead try to seize the whole of the south-east, cutting Ukraine off from the sea, according to people involved in trying to end the war.

Ukraine is confident it can push Russian troops back further after defeating Putin’s initial plan to rapidly seize the country, but officials are increasingly worried that Moscow could resort to tactical nuclear weapons if it suffers further setbacks, two of the people said.

In a meeting with Michel in Kyiv on Wednesday, Zelensky said Ukrainian public opinion did not support continuing the peace talks, adding that he was conscious that fighting Putin was more popular than making concessions, according to a person briefed on their conversation.

Erdogan spoke to Zelensky on Sunday in a drive to revive the stalled negotiations. The Turkish leader said Ankara stood ready to help, according to a statement. Erdogan said on Friday that he also hoped to speak to Putin in the days ahead.

Putin’s spokesman Dmitry Peskov and a representative for Abramovich did not immediately respond to requests for comment.

Additional reporting by Laura Pitel in Ankara