The Romanian Air Force's surveillance system detected an aerial object that looked like a weather balloon flying in the country's airspace, the defence ministry said on Tuesday.
Two MiG 21 LanceR jets were scrambled to the area in southeast Romania 10 minutes after the sighting but could not confirm the object's presence, the ministry said, adding the balloon was flying at an altitude of 11,000 metres.
The sighting in Romania comes amidst a diplomatic spat between the United States and China after the US shot down a suspected Chinese spy balloon on February 4.
The defence ministry said the crews of the aircraft stayed in the area for 30 minutes before returning to base after not getting visual, or radar confirmation, of the target.
The sighting in Romania also occurred on the same day that Moldova, which borders Romania and Ukraine, briefly closed its air space for undisclosed safety reasons, although the Romanian ministry did not link the events in its statement. (Reporting by Luiza Ilie; Writing by Jason Hovet; Editing by Sharon Singleton)