Several Russian airlines are operating with unusually high numbers of grounded aircraft as Western sanctions continue to complicate access to spare parts and maintenance, the Kommersant newspaper reported Monday.

An analysis by the business daily found that about one-fifth of the aircraft operated by Russia's 11 largest airlines were not in service this summer. However, that figure is heavily skewed by a small number of carriers facing acute maintenance challenges. Excluding state-controlled Aeroflot Group, which has kept most of its fleet flying, nearly 30% of aircraft operated by the remaining major airlines were grounded, according to the newspaper.

The figures underscore the uneven impact of sanctions imposed after Russia's full-scale invasion of Ukraine. While flagship carriers such as Aeroflot and low-cost subsidiary Pobeda continue to operate most of their fleets, airlines with larger numbers of newer Western-built aircraft have struggled to obtain engines, spare parts and maintenance support.

S7, Russia's largest private airline, has been hit the hardest among the country's major scheduled carriers.

Around 32% of its fleet was out of service, largely because of engine problems affecting Airbus A320neo aircraft, Kommersant reported.