Ministry of Defence in London on Monday said the Russian air force has been under increasing pressure in the war against Ukraine.

According to a daily British intelligence update, in the past 10 days, Russia has apparently lost four fighter jets, bringing the total to 55 aircraft since the invasion began at the end of February.

“The increase in losses may be partly due to the Russian air force taking greater risks to support ground forces under pressure from Ukrainian advances at close range,’ it said.

Added to this was the poor situational awareness of Russian pilots. Some aircraft, it said, had entered denser air defence zones because of the fast-moving front over Ukrainian-controlled territory.

“Russia’s continued lack of air superiority remains one of the most important factors underpinning the fragility of its operational design in Ukraine,” the ministry said.

The Ministry of Defence had been publishing daily updates based on intelligence reports on the progress of the war against Ukraine since Russia launched its invasion in February.

Moscow accused London of a targeted disinformation campaign.