Belarus' KGB state security service spokesman Dmitry Pobyarzhin speaks during a briefing in Minsk, Belarus November 20, 2017. REUTERS/Vasily Fedosenko

MINSK (Reuters) - Belarus’s KGB state security service said on Monday it had uncovered a spy ring working for the Ukrainian defence ministry that had been set up by a detained Ukrainian radio correspondent.

Minsk-based journalist Pavlo Sharoyko was arrested in October and charged with being an undercover intelligence officer, KGB spokesman Dmitry Pobyarzhin said in a briefing.

“In Belarus, Sharoyko built a network of agents made up of Belarussian citizens, who carried out his assignments for monetary compensation,” Pobyarzhin said.

An adviser to the embassy in Minsk, Ukrainian Ihor Skvortsov, has been declared persona non grata - banned from the country - as he is believed to be Sharoyko’s handler, Pobyarzhin said.

The Ukrainian defence ministry denied the allegations against Sharoyko who it said had worked as a spokesman for the ministry before switching to journalism in 2009.

“The information contained in the (KGB) statement is not true,” it said.

The Ukrainian foreign ministry declined immediate comment. Sharoyko and Skvortsov could not be reached for comment.

The case could put further pressure on relations between Minsk and Kiev that were tested earlier this year when Belarus hosted large-scale joint military exercises with Russia.

September’s Zapad-2017 (“West-2017”) war games unnerved Ukraine and NATO member states on Europe’s eastern flank, which feared the exercises could be a rehearsal or cover for a real offensive.