(Reuters) -Ukraine's overnight drone strikes have forced a temporary suspension of flights in all airports serving Moscow and the country's second-largest city St. Petersburg, but caused no damage, Russian officials reported on Tuesday.

Russian air defence units destroyed a total of 102 Ukrainian drones overnight, the Russian defence ministry - which reports only how many were downed, not the number Ukraine launched - said on the Telegram messaging app.

Nearly half of the drones were destroyed over the Bryansk region that borders Ukraine, the ministry said. Three drones were downed over the Moscow region and two over the Leningrad region, of which St. Petersburg is the regional capital.

Russia's civil aviation authority Rosaviatsia temporarily halted flights at all four major airports serving Moscow and St. Petersburg's Pulkovo Airport, as well as at airports in nine other cities to ensure safety, it said on Telegram.

Flights in Moscow and some other cities were restored by Tuesday morning, but restrictions were still in place in St. Petersburg at 0430 GMT.

Regional governors, who wrote about the attacks on Telegram, did not report any damage caused by the attacks.

(Reporting by Lidia Kelly in Melbourne; Editing by Chris Reese and Saad Sayeed)