International Red Cross representatives in an undisclosed location in the Sumy region check body bags that contain the remains of servicemen. [AFP]

Ukraine said Friday it received the bodies of 250 slain soldiers in one of the largest exchanges with Moscow since Russia launched its invasion of Ukraine in February 2022.

Kyiv said it handed over the remains of 38 Russian soldiers in the deal, which was mediated by the International Red Cross.

Some of those who returned to Ukraine were soldiers who had fought in the southern port city of Mariupol, the scene of an intense standoff from February to May of 2022, according to Agence France-Presse reports.

Russia captures 5 Ukrainian settlements

On the battlefront Friday, Russian forces continued their assault on several fronts in Ukraine's eastern Donetsk region, including the city of Pokrovsk, a strategic logistics hub.

Ruslan Muzychuk, a spokesperson for Ukraine's National Guard, said in televised remarks that Russian forces are using warplanes and artillery fire to support infantry assaults around the city.

"It's a significant threat ... because the Pokrovsk and Toretsk fronts are taking a large share of the daily aviation strikes carried out on the positions of Ukrainian defenders."

Pasi Paroinen, an analyst with the Black Bird Group, told Reuters news agency that Russian forces gained about 57 square kilometers in the past week after making only modest gains in June.

The Russian Defense Ministry said Russian forces have captured five Ukrainian settlements in the past week.

More Ukrainians expected to emigrate

In other developments, Ukraine's central bank said Russian attacks on energy centers and a struggling economy will likely lead to higher emigration levels this year.

"The worsening of the energy situation and slow normalization of the economic conditions will lead to a larger outflow of migrants abroad in 2024 and 2025 than previously expected," the National Bank of Ukraine said in a report released Thursday.

It predicted a net outflow of 400,000 people this year and attributed the higher levels to "significant destruction of the Ukrainian energy system, which is accompanied by long power outages and increased risks for the [winter] heating season."

Estimates of Ukraine's population for 2023 range from 28 million to 34 million, down from a population of 41 million before the start of the war in 2022.