The Russian Defense Ministry said on Saturday that Ukraine is refraining from setting a date for the new round of prisoner exchange, agreed by Russian and Ukrainian delegations at talks in Istanbul earlier this week.
"The Russian side has provided the Ukrainian side with a list of 640 names, but the Ukrainian side is currently refraining from setting a date for the return of these individuals and the transfer of the corresponding number of Russian prisoners of war," the ministry said in a statement, citing Lieutenant General Alexander Zorin.
Kremlin aide Vladimir Medinsky said earlier on Saturday that Ukraine had unexpectedly postponed exchanging prisoners of war and accepting the bodies of killed soldiers for an indefinite period.