Russia’s military has been ordered to pull out of the Ukrainian city of Kherson, the only regional capital it captured after invading in February.
Russia’s commander in Ukraine, Gen Sergei Surovikin, said it was no longer possible to keep supplying the city.
The withdrawal means Russian forces will pull out entirely from the western bank of the River Dnipro.
It is a significant blow as Russia faces a Ukrainian counter-offensive.
For the Kremlin, it is also an embarrassment, says BBC Russia Editor Steve Rosenberg.
The military’s top brass were seen making the decision on Russian state TV, with Gen Surovikin reporting on the situation on the ground in Kherson.
President Vladimir Putin did not take part in the staged event. The architect of Russia’s failing war in Ukraine appeared to have left the announcement to his generals.
It was Mr Putin who announced Russia’s annexation of Kherson, and three other occupied regions, at the end of September.
Russian forces swept across southern Ukraine from annexed Crimea at the start of the war, seizing Kherson city in early March.
But their decision to pull back across the Dnipro river was treated with caution by Ukrainian officials. Presidential adviser Mykhailo Podolyak warned that it was premature to treat the announcement at face value.
