Ukrainian President Volodymyr Zelensky says he is ready to meet Russian President Vladimir Putin "personally" in Istanbul on Thursday for talks over ending the war.

His post on X came shortly after Donald Trump demanded that Ukraine agree to Putin's offer of direct talks between the two countries in Turkey.

"There is no point in prolonging the killings. And I will be waiting for Putin in Türkiye on Thursday. Personally," Zelensky wrote.

He had earlier said his country was open to talks with Russia, but only after a ceasefire was in place.

Western powers called for a 30-day pause in fighting to begin on Monday after European leaders spearheading the so-called "coalition of the willing" met in Kyiv on Saturday.

Putin's offer of direct talks followed that intervention.

On Sunday, Trump then posted on social media that Ukraine should agree to this "immediately" and it would provide clarity on whether there was a way to end the war.

"At least they will be able to determine whether or not a deal is possible, and if it is not, European leaders, and the US, will know where everything stands, and can proceed accordingly" he said, adding: "Have the meeting, now!"

In his post on X, Zelensky said he hoped Russia would agree to the ceasefire before the talks.

"We await a full and lasting ceasefire, starting from tomorrow, to provide the necessary basis for diplomacy," he said.

In a late-night address on Saturday, Putin invited Ukraine to take part in "serious negotiations" over the war, which began with Russia's full-scale invasion of Ukraine in 2022.

Putin said he could "not rule out" the possibility that the talks could result in Russia and Ukraine agreeing "a new truce" - but did not address the calls for a 30-day ceasefire directly.

The Russian leader said: "This would be the first step towards a long-term, lasting peace, rather than a prologue to more armed hostilities after the Ukrainian armed forces get new armaments and personnel, after feverish trench-digging and the establishment of new command posts."

Moscow has previously said that before Russia could consider a ceasefire, the West must first halt its military aid to Ukraine.

On Saturday, the Ukrainian president played host in Kyiv to UK Prime Minister Sir Keir Starmer, France's Emmanuel Macron, Germany's Friedrich Merz and Poland's Donald Tusk, who later called Trump to discuss their plan.

Sir Keir later told the BBC the US president was "absolutely clear" that their suggestion of an immediate ceasefire was a "demand that must be met".

Appearing at a news conference with Zelensky, they warned that "new and massive" sanctions would be imposed on Russia's energy and banking sectors should Putin not agree to the unconditional 30-day ceasefire "in the air, at sea and on land".

Russia and Ukraine last held direct negotiations in March 2022 in Istanbul, shortly after Moscow launched its invasion.

More than three years later, both sides have agreed, in principle, to resume negotiations. But talks and a deal are very different things. Both sides seemingly retain their red lines, which are as far apart as ever.