Russian President Vladimir Putin has proposed direct talks with Ukraine in Istanbul on May 15, “without preconditions” to achieve “lasting peace” and “eliminate the root causes” of the three-year conflict, Al Jazeera reported.

The offer, delivered early on Sunday, came hours after the leaders of Ukraine, France, Germany, Poland and the United Kingdom called for an unconditional 30-day ceasefire.

The leaders, who were meeting in Kyiv, said their call is backed by United States President Donald Trump and threatened “massive” new sanctions on Moscow if it did not agree with their plan.

Putin, however, rejected that proposal, slamming  European “ultimatums” and “anti-Russian rhetoric”, before outlining the counter-proposal for renewed Russia-Ukraine negotiations.

“We are proposing that Kyiv resume direct negotiations without any preconditions,” the Russian president told reporters. “We offer the Kyiv authorities to resume negotiations already on Thursday, in Istanbul.”

Turkish President Recep Tayyip Erdogan on Sunday told Russian and French leaders that a “historic turning point” has been reached in efforts to end the Russia-Ukraine war and that Ankara was ready to host talks between the two warring parties, his office said.