Russian President Vladimir Putin declared a unilateral Easter ceasefire in Ukraine, ordering his forces to end hostilities at 6 p.m. Moscow time (1500 GMT) on Saturday until the end of Sunday.

President Volodymyr Zelenskiy said Ukrainian air defence units were repelling an attack by Russian drones on Saturday, saying that showed true Moscow's attitude to Easter and the lives of people.

"Based on humanitarian considerations ... the Russian side announces an Easter truce. I order a stop to all military activities for this period," Putin told his military chief, Valery Gerasimov, at a meeting in the Kremlin.

"We assume that Ukraine will follow our example. At the same time, our troops should be prepared to repel possible violations of the truce and provocations by the enemy, any aggressive actions," Putin added.

U.S. President Donald Trump and Secretary of State Marco Rubio had said on Friday the United States would walk away from efforts to broker a Russia-Ukraine peace deal unless there are clear signs of progress soon.

The full-scale war began when Putin ordered thousands of Russian troops across the border into Ukraine on February 24, 2022.

Putin has said repeatedly that he wants an end to the war. He has demanded that Ukraine must officially drop its ambitions to join NATO and withdraw its troops from the entirety of the territory of four Ukrainian regions claimed by Moscow.

Kyiv has broadly rejected those terms as tantamount to surrender.

Putin told Gerasimov on Saturday that Russia welcomed efforts from the U.S., China and BRICS countries to find a peaceful settlement to the conflict.

The Russian Defence Ministry said it had given instructions on the ceasefire to all group commanders in the area of the "special military operation", the Kremlin's term for the war.

Russian troops will adhere to the ceasefire provided it is "mutually respected" by Ukraine, the ministry said in a statement.

Separately, the Russian Defence Ministry said Russia and Ukraine conducted a prisoner of war swap of 246 prisoners each on Saturday, mediated by the UAE.

The Russian POWs are in Belarus, the ministry said, where they were being provided with medical and psychological care.