- Russia has probably lost one third of the invasion force it deployed in Ukraine, the UK said.
- It said Moscow has lost critical equipment for its push into the Donbas, including recon drones.
- Russia's advance is behind schedule, and is likely to stay that way over the next 30 days, it added.
Russia has likely lost a third of the ground troops it deployed in February for the invasion of Ukraine, according to the UK's defense ministry.
Moscow's renewed offensive in eastern Ukraine — the invasion's focus for the last month — has also "lost momentum and fallen significantly behind schedule," the UK defense ministry tweeted on Sunday.
"Despite small-scale initial advances, Russia has failed to achieve substantial territorial gains over the past month whilst sustaining a high level of attrition," it said in its assessment. "Russia has now likely suffered losses of one-third of the ground combat force it committed in February."
As such, Russia is unlikely to dramatically accelerate its advance over the next 30 days, the tweet continued.
The ministry said losing "critical enablers" such as "bridging equipment, surveillance, and reconnaissance drones" would further delay the Russian advance, adding that Moscow's drones have been vulnerable to Ukraine's anti-air weapons.
The ministry's assessment said poor morale and reduced combat effectiveness have also "increasingly" impacted Moscow's forces.
On the same day, NATO Secretary-General Jens Stoltenberg said the war "is not going as Moscow had planned," according to the Associated Press.
"Ukraine can win this war," Stoltenberg said, per the AP.
Ukraine's military held off an advance into the capital of Kyiv in the north and has reportedly killed over 15,000 Russian troops in the last three months.
Russia has seized territories in Ukraine's southeast and the eastern Donbas region, which is partially held by pro-Russian separatists but has apparently withdrawn from the city of Kharkiv in the northeast.