Russia on Saturday accused Ukraine of postponing a large-scale exchange of captured soldiers, hours after Moscow's army launched a barrage of missiles, drones and bombs across the country.
Kyiv and Moscow agreed to release all wounded soldiers and those aged under-25 that had been captured, with both sides saying the exchange was set for this weekend.
The POW swap -- to involve more than 1,000 people on each side -- along with an agreement to hand over the bodies of thousands of killed soldiers was the only concrete outcome of a second round of peace talks in Istanbul on Monday.
Russia has rejected Ukraine's calls for an unconditional ceasefire, drawing accusations Moscow has no desire to halt its three-year invasion.
"The Ukrainian side has unexpectedly postponed for an indefinite per