Russia and Ukraine each released hundreds of prisoners of war on Friday at the start of the biggest swap of captives of the conflict so far.
Russia and Ukraine each released 270 soldiers and 120 civilians on Friday.
Ukrainian president Volodymyr Zelensky confirmed that Ukraine had returned 390 people from Russian captivity.
Russia and Ukraine had each agreed after two hours of peace talks in Istanbul last week to swap 1,000 prisoners.
It was the only concrete step towards peace to emerge from their first direct talks in more than three years.
The exchange took place on the Ukrainian border with Belarus.
The Russian ministry said the releases were due to continue in coming days.
It said Russian soldiers released including those captured by Ukrainian forces in Russia's Kursk border region during Kyiv's offensive in recent months.
They were currently on Belarusian territory and were to be taken to Russia for medical checks and treatment, the ministry said.
President Zelensky said “We are bringing our people home,” on social media.
“We are verifying every surname, every detail about each person”, he said.
Ukraine's co-ordination headquarters for prisoners of war said the 270 Ukrainian servicemen released had fought in regions across the east and north, from Kyiv, Chernihiv and Sumy to Donetsk, Kharkiv and Kherson.
Families of Ukrainian soldiers held by Russia gathered in northern Ukraine on Friday hoping that their sons and husbands would be among those released.
Referring to the prisoner swap earlier on Friday, Trump wrote on Truth Social: "Congratulations to both sides on this negotiation. This could lead to something big???"
The prisoner swap has raised hopes that further talks could take place over a potential ceasefire in the conflict.
Ukraine says it is ready for a 30-day ceasefire immediately.
Russia, which launched the war by invading its neighbour in 2022 and now occupies about a fifth of Ukraine, says it will not pause its assaults until conditions are met first. A member of the Ukrainian delegation called those conditions "non-starters".
Trump, who has shifted US policy from supporting Ukraine towards accepting some of Russia's account of the war, had said he could tighten sanctions on Moscow if it blocked peace. But after speaking to Putin on Monday he decided to take no action for now.
Moscow says it is ready for talks while the fighting goes on, and wants to discuss what it calls the war's "root causes", including its demands Ukraine cede more territory, and be disarmed and barred from military alliances with the West. Kyiv says that is tantamount to surrender and would leave it defenceless in the face of future Russian attacks.
Meanwhile, fighting has continued.
Russia claimed on Friday to have captured a settlement called Rakivka in Ukraine's northeastern Kharkiv region.
The governor of Ukraine's Odesa region, Oleh Kiper, said Russia had struck port infrastructure there with two missiles on Friday afternoon, killing one person and wounding eight.
