The UK MOD said Russia looked unlikely to make any big gains in Ukraine for months.
It's highly unlikely that Russia can generate an effective striking force in the coming months, it said.
Ukraine, meanwhile, predicted an increase in its offensive moves once the ground freezes.
The British defense ministry said in an intelligence update on Monday that "Russian ground forces are unlikely to make operationally significant advances within the next several months."
On December 3, Avril Haines, the US National Intelligence Director, said that winter conditions are expected to slow the war, and that there was already a "reduced tempo."