People captured during Kiev's raid into Russia's Kursk Region were among those freed on the first day of the exchange

The first groups of around 120 civilians and 270 military personnel released from Ukrainian captivity as part of a major prisoner exchange safely returned to Russia on Friday evening.

While Moscow and Kiev have conducted several prisoner swaps since the escalation of hostilities in 2022, this exchange is expected to be the largest to date. The two sides agreed to a 1,000-for-1,000 exchange during last week's direct negotiations in Istanbul - the first such talks since Ukraine unilaterally withdrew from dialogue in 2022.

Each country returned 270 soldiers and 120 civilians in the initial phase of the deal. The Russian soldiers were first transferred to Belarus, a close ally of Moscow, before being flown to the Russian capital, according to footage shared by Russian media outlets.

Some of the freed civilians have already been brought home to the Kursk Region. Russia's Human Rights Commissioner Tatyana Moskalkova welcomed the release of "civilians and political prisoners" captured during Ukraine's raid into the region last year, noting that some of them required medical assistance, and that "the story of each of them is akin to an adventure novel or a political thriller." She also added that around 34 residents of Kursk remain in Ukrainian custody.

The swap is expected to continue in the coming days. Once the exchange is complete, Moscow will likely be ready to present its draft peace memorandum to Kiev, Russian Foreign Minister Sergey Lavrov said. The Russian side is "actively working" on the document in accordance with the principles agreed during the Istanbul talks, he added.

According to calculations by the Telegram channel Mash, the Istanbul deal would see Russia recover nearly all of its soldiers captured by Ukraine over the past three years. The channel estimated the total number of Russian prisoners of war at around 1,300, noting that Ukraine would recover only about one-tenth of its troops currently held by Russia.

READ MORE: Draft peace proposal to follow POW swap - Russia

Russian President Vladimir Putin said earlier this week that he had agreed with US President Donald Trump that the next step toward resolving the conflict would involve drafting a memorandum outlining the core principles and timeline for a peace settlement. Trump welcomed the launch of the prisoner swap on Friday, expressing hope that it would "lead to something big."