Belarus has told some Ukrainian diplomats to leave the country and is closing its neighbour's consulate in the city of Brest, the country's BelTA news agency reported on Wednesday.
On Tuesday the Belarusian security service, the KGB, accused eight Ukrainian diplomats of espionage.
Russia has used Belarusian territory as a staging post for its invasion of Ukraine.
(Reporting by Reuters; Editing by Conor Humphries)