Kyiv, Ukraine — Ukrainian President Volodymyr Zelensky accused Russia on Tuesday of delaying peace talks in a bid to pursue its three-year invasion, even as US President Donald Trump pushes for an immediate ceasefire.

Trump spoke by phone on Monday to both Zelensky and Russia's Vladimir Putin, after Russian and Ukrainian officials met in Istanbul on Friday for their first direct talks on the conflict in three years.

Neither the talks nor the phone call resulted in Russia offering any concessions, and Putin has consistently rejected proposals for a 30-day truce put forward by Kyiv and its Western allies.

US Secretary of State Marco Rubio insisted Tuesday that Trump had himself offered no concessions to Putin, amid frustration in Washington and Kyiv at Russia's apparent stalling.

"It is obvious that Russia is trying to buy time in order to continue its war and occupation," Zelensky said in a post on social media.

Trump framed his two-hour conversation with Putin, the third so far this year, as a breakthrough.

The Republican is seeking an elusive deal to end the war that he had promised on the election campaign trail to solve in 24 hours.

But Putin again rebuffed the call for a full, immediate and unconditional ceasefire, instead saying he was ready to work with Ukraine on a "memorandum" outlining a possible roadmap and different positions on ending the war.

Moscow is feeling confident, with its troops advancing on the battlefield and Trump having resumed dialogue with Putin after almost three years of the West shunning the Kremlin chief.

"The memorandum buys time for Russia," Russian political analyst Konstantin Kalachev told AFP.

"The cessation of hostilities is not a condition for it, which means that Russia can continue its offensive," he added.

Zelensky said on Monday he had no details of what this "memorandum" would be but was willing to look at Russia's ideas.

Russia invaded Ukraine in February 2022 and has since destroyed swathes of the country's east, killed tens of thousands and now controls around one-fifth of its territory.

Trump's no 'messiah'

People who spoke to AFP both in Kyiv and Moscow were sceptical about peace prospects and thought the Putin-Trump call had not brought them closer.

"I never had any faith in him and now I have none at all," a retired teacher Victoria Kyseliova told AFP in Kyiv, when asked if she was losing confidence in Trump.

Vitaliy, a 53-year-old engineer from Kyiv, said Trump was no "messiah" and that his flurry of diplomacy has changed little. 

Ukrainian political analyst Volodymyr Fesenko said Trump's latest calls had only added to the uncertainty.

"This conversation not only failed to clarify the future of the negotiations but further confused the situation," he said.

He said Trump had fallen for Putin's tactics of trying to use talks "as a cover to continue and intensify the war".

In Moscow, there was defiance and confidence.  

"I believe that we don't need these negotiations. We will win anyway," Marina, a 70-year-old former engineer, told AFP.

Sanctions push

Ukraine and Europe are trying to put pressure on Trump to impose on Moscow a new package of massive sanctions after Putin declined to travel to Turkey for face-to-face talks with Zelensky.

Kyiv accused Moscow's negotiators of making unrealistic demands at the Istanbul talks, including sweeping territorial claims that Ukraine has repeatedly rejected.

Zelensky said on Monday that Kyiv and its allies needed to "work hard" to convince Trump of the need for more sanctions.

On Tuesday, the European Union formally adopted its 17th round of sanctions on Moscow, targeting 200 vessels of Russia's so-called shadow maritime fleet, and drawing ire from Russia.

"Western politicians and the media are making titanic efforts to disrupt the constructive dialogue between Russia and the United States," said Kirill Dmitriev, the head of Russia's Direct Investment Fund and lead economic negotiator with the United States.

Russia has successfully withstood sanctions, rerouting its vital oil and gas supplies to India and China.

Trump has suggested a "large-scale trade" with Russia once the war is over, but US top diplomat Marco Rubio denied Tuesday that Trump had offered concessions.

"He hasn't gotten a single concession," Rubio said of Putin.

Russia's key ally China said on Tuesday it also backed direct dialogue between the warring sides.

"It is hoped that the parties concerned will carry on with the dialogue... to reach a fair, lasting and binding peace agreement acceptable to all parties," said foreign ministry spokeswoman Mao Ning.

(Source: Stanislav DOSHCHITSYN, AFP)