Russia has "definitively" lost the initiative in the battle for the Donbas in Ukraine, according to western officials.
Moscow will not take the eastern industrial heartland in the "immediate future", one official said, but "they are not just going to give up and go home".
They said there has been "wax and wane" in the war in Ukraine, and Russia has the capacity to "adapt and adjust what they are doing".
Earlier this month, western officials said the sustainability of Russia's attacks on Ukraine was "challenging", with Moscow making "genuine headway" on the objective it claimed was the rationale for the invasion – the supposed liberation of the Donbas.
But a western official said on Wednesday that Russia has "definitively lost the initiative" in the battle for the region.
They said it is believed that securing the full extent of Donetsk Oblast remains the "minimum political objective of the Donbas campaign", but it looks "increasingly unlikely" that Russia will achieve this in the next several months.
Asked if Russia's loss of initiative in the battle for the region represented a turning point in the war, the official said there had been "wax and wane" so far.
Watch: Ukrainians on a mission to recapture Kherson.
They said Moscow is unlikely to "give up and go home" if it does not feel the Donbas is "winnable", but will "think and adapt to what they can do next".
It comes as Ukrainian artillery hit a strategic bridge key for Russia to supply its forces in the south.
The initial assessment is that the crossing is "completely unusable" for the time being, the official said.
A Ministry of Defence (MOD) intelligence update on the situation in Ukraine said that Russian private military company Wagner had "likely succeeded in making tactical advances in the Donbas around the Vuhlehirska Power Plant and the nearby village of Novoluhanske".