Dmitry Utkin died in a plane crash that killed all 10 people on board, including Wagner leader Yevgeny Prigozhin and his other top lieutenants.
The president gave no details but the remark was the clearest hint that Ukraine was responsible for a wave of drone attacks on a Russian airport.
The showpiece event took place at Ayr Racecourse in April.
Drones struck an airport in western Russia’s Pskov region, according to the Kremlin.
Drones hit an airport in Russia’s western Pskov region near the border with Estonia and Latvia.
Meanwhile, Russian forces targeted central and northern regions of Ukraine with cruise missiles overnight.
The shelling comes as UK officials say Russian forces may try to retake the region.
Yevgeny Prigozhin is presumed to have died in a plane crash.
Details of the assessment surfaced as Vladimir Putin referred to ‘serious mistakes’ made by the head of the Wagner Group of mercenaries.
Mr Putin described Yevgeny Prigozhin as ‘a man of difficult fate’ who had ‘made serious mistakes in life’.
Russia’s civil aviation agency said Wagner chief Yevgeny Prigozhin and six top lieutenants were on a business jet that crashed on Wednesday.
The founder of the Wagner military company has been the subject of speculation since he mounted a mutiny against the Kremlin.
The report of General Sergei Surovikin’s dismissal came after weeks of uncertainty about his fate following the short-lived rebellion.
A three-hour night-time Russian drone attack caused a blaze at grain facilities, Odesa Regional Military Administration head Oleh Kiper said.
Lui Sai-yu lost his appeal against a five-year sentence imposed after he pleaded guilty to inciting secession in the city.
