Russian transportation authorities on Wednesday vowed to prevent any disruptions to domestic air travel after Ukrainian President Volodymyr Zelensky warned the day before that Kyiv's drone attacks were making Russian airspace too dangerous for flying.

Transportation Minister Andrei Nikitin said that civil aviation authorities are "constantly improving flight safety and airport security requirements, and we have solutions for all of this," as quoted by the news agency Interfax.

"We are working in close contact with the Defense Ministry and the Russian National Guard. And I believe that we will not allow any significant disruption to civil aviation," Nikitin added.

Following Zelensky's warning, Ukrainian Foreign Minister Andrii Sybiha said Kyiv had officially notified the International Civil Aviation Organization that Russian airspace is unsafe for commercial flights.

Those comments appeared to have an almost immediate impact on air travel inside Russia. On Wednesday, Moscow's Sheremetyevo airport showed 21 canceled flights and 235 delays, while Vnukovo airport saw 22 canceled flights and 94 delays, according to the flight tracking service Flightradar24.

Turkish carrier Pegasus Airlines said it had canceled some flights to Russia for "technical and operational" reasons but did not provide further information.

Vnukovo airport said Pegasus Airlines had canceled six arriving and six departing flights at the hub on Tuesday. The carrier said overnight flights into Wednesday would be impacted, but other ongoing flights were "operating as scheduled."

Aviation risk advisory firm Osprey Flight Solutions said in an alert to clients that while the majority of Ukraine's drone and missile strikes were likely to occur within 300 kilometers (186 miles) of the border, daily attacks deeper inside Russia were near-certain through 2026, including near Moscow and St Petersburg.

"There is also a realistic possibility that the frequency of Ukrainian strikes will continue to increase in the short term deep inside Russian territory," the alert said. "It is assessed that miscalculation and/or misidentification is likely in areas related to the Ukraine conflict."