(Reuters) -Russia will spare the lives of Ukrainian soldiers in its western Kursk region if Kyiv tells them to surrender, President Vladimir Putin said on Friday after U.S. President Donald Trump urged him to avoid a "horrible massacre" there.

By Steve Holland, Dmitry Antonov and Andrew Osborn WASHINGTON/MOSCOW (Reuters) -U.S. President Donald Trump urged Russia's Vladimir Putin on Friday to spare Ukrainian troops being pushed back out of Russia's Kursk region and said there was a "very good chance" the war could end.

President Vladimir Putin called on Friday for beleaguered Ukrainian troops in the Russian region of Kursk to "surrender" as Ukraine's President Volodymyr Zelensky accused the Russian leader of seeking to sabotage a ceasefire initiative.

He added that he had requested that Putin spare the lives of "completely surrounded" Ukrainian troops, apparently referring to Ukrainian forces being pushed back out of the Kursk region, their only foothold on Russian territory.

Vladimir Putin told a news conference that he agreed with the idea of a ceasefire, but he immediately spelled out tough conditions that appeared to rule out agreement.

President Donald Trump on Saturday said he was naming Keith Kellogg his special envoy for Ukraine, narrowing the retired general’s portfolio after reports he was sidelined during recent US-Russia talks at the Kremlin’s request.

Russia is planning to strike in Ukraine's Sumy region, the Ukrainian president wrote on Saturday in an X post.