A three-day ceasefire has been agreed by the leaders of Russia and Ukraine, as well as an exchange of prisoners, following a request from Donald Trump.
The ceasefire will run from Saturday until Monday and has been confirmed by Volodymyr Zelenskyy and Vladimir Putin's foreign policy aide, Yuri Ushakov.
The US president said it could represent the "beginning of the end" of the years-long war.
"This Ceasefire will include a suspension of all kinetic activity, and also a prison swap of 1,000 prisoners from each Country," Mr Trump wrote on Truth Social.
"This request was made directly by me, and I very much appreciate its agreement by President Vladimir Putin and President Volodymyr Zelenskyy."
Agreements on extending the ceasefire and exchanging prisoners were reached in telephone calls with the Trump administration, Mr Ushakov said.
Moscow and Kyiv will also carry out a prisoner exchange in the format of "one thousand for one thousand" during this period, he added.
Mr Zelenskyy said in an earlier online post: "I thank the president of the United States and his team for their productive diplomatic involvement."
But he added pointedly: "We expect the United States to ensure that the Russian side fulfils these agreements. Glory to Ukraine!"
Saturday is Victory Day in Russia, a holiday that commemorates its triumph over Nazi Germany 81 years ago in the Second World War.
This year's parade in Moscow - usually a display of Russian military might with intercontinental ballistic missiles and tanks - will have no military equipment on show due to the threat of attack from Ukraine.
"In general, everything is as usual, except for the demonstration of military equipment," Mr Ushakov said.
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Addressing the possibility of an attack, Mr Zelenskyy said the promise of a prisoner swap was more important.
He said: "Red Square matters less to us than the lives of Ukrainian prisoners of war who can be brought home."
He subsequently issued a presidential decree declaring Red Square off-limits for Ukrainian strikes for the duration of the event.
Earlier, a unilateral ceasefire in Ukraine that Russia had announced for Friday and Saturday quickly unravelled.
Moscow and Kyiv blamed each other for the continued fighting, just as they did when Ukraine's own unilateral ceasefire quickly collapsed earlier in the week.
The accusations reflect the deep-seated lack of trust between the two nations, which has so far thwarted US-led diplomatic efforts to find a peace settlement.
Four years since the 2022 Russian invasion of Ukraine, the two sides are still bombarding each other with missiles, drones and artillery, with no end to the war in sight.
The Russian Defence Ministry said 264 Ukrainian drones had been downed in the early hours of Friday.
Moscow mayor Sergei Sobyanin said the capital had been targeted, and officials said the Urals region of Perm had been hit by drones.
Ukraine said it had struck a Russian oil refinery in Perm for the second day running, and hit another oil facility in the city of Yaroslavl.
(c) Sky News 2026: Three-day ceasefire between Russia and Ukraine announced
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