Putin open to peace but rapid progress is hard: Kremlin

President Vladimir Putin is open to peace in Ukraine and intense work is going on with the United States, but the conflict is so complicated that the rapid progress that Washington wants is difficult to achieve, the Kremlin says.

US President Donald Trump, who says he wants to be remembered as a peacemaker, has repeatedly said he wants to end the "bloodbath" of the more than three-year war in Ukraine.

But Washington has been signalling that it is frustrated by the failure of Moscow and Kyiv to reach terms to end the deadliest land war in Europe since World War II.

"The (Russian) president remains open to political and diplomatic methods of resolving this conflict," Kremlin spokesperson Dmitry Peskov told reporters.

He noted that Putin had expressed a willingness for direct talks with Ukraine, but that there had been no answer yet from Kyiv.

Russia's aims had to be achieved either way, he added, saying Moscow's preference was to achieve those aims peacefully.

"We understand that Washington is willing to achieve a quick success in this process," Peskov said in English. But news agency TASS quoted Peskov as saying the root causes of the Ukraine war were too complex to be resolved in one day.

Putin's decision to send tens of thousands of troops into Ukraine in 2022 triggered the worst confrontation between Moscow and the West since the 1962 Cuban Missile Crisis.

Former US President Joe Biden, Western European leaders and Ukraine cast the invasion as an imperial-style land grab and repeatedly vowed to defeat Russian forces.

Putin casts the war as a watershed moment in Moscow's relations with the West, which he says humiliated Russia after the Soviet Union fell in 1991 by enlarging NATO and encroaching on what he considers Moscow's sphere of influence, including Ukraine.

Putin in March said Russia supported a US proposal for a ceasefire in Ukraine in principle, but that fighting could not be paused until a number of crucial conditions were worked out or clarified.

On Monday, Putin declared a three-day ceasefire in May to coincide with the 80th anniversary of the victory of the Soviet Union over the Nazis in World War II.

Ukrainian President Volodymyr Zelenskiy has said that progress in resolving the war depended on Russia taking the first step of agreeing to an unconditional ceasefire.

Trump said on Tuesday he thought that Putin wants to stop the war in Ukraine, adding that if it was not for him Russia would try to take the whole of Ukraine.

"If it weren't for me, I think he'd want to take over the whole country," Trump said.

US Secretary of State Marco Rubio said now was the time for concrete proposals from Moscow and Kyiv to end the war and warned that the US will step back as a mediator if there is no progress.

Trump refused to answer a question about whether the United States would halt military aid to Ukraine if Washington walked away from talks.

At a United Nations Security Council meeting, US diplomat John Kelley blamed Russia for the continuing bloodshed, saying it had "regrettably" carried out high-profile strikes "causing needless loss of life, including of innocent civilians".

"Right now, Russia has a great opportunity to achieve a durable peace," Kelley said, while adding the burden for ending the war rests with Russia and Ukraine.

On the battlefront, swarms of Russian drones attacked the Ukrainian cities of Kharkiv and Dnipro, killing at least one person and injuring at least 50, officials said.

And a Ukrainian drone slammed into a car on a highway in Russia's border Belgorod region, killing two people and injuring three in the first of a series of attacks during the day, according to the regional governor.

with AP