The EU and Nato state, which shares a 650km border with Ukraine, has had Russian drone fragments fall on its territory repeatedly over the past year and a half as Moscow attacks Ukrainian port infrastructure.

The ministry said the radar first picked up the signal at 1904 GMT, 15km east of Chilia Veche in Tulcea county.

It alerted the population of the county to take cover and began procedures to scramble fighter jets, but the radar lost the signal at 1909 GMT.

“There is no information about a possible target impact on national territory,” the ministry said.

In October, radar picked up several drone signals on separate days breaching Romanian airspace, with fighter jets unable to see them and no crash sites identified, and officials said the incidents might have been examples of cyber interference.