BUDAPEST (Reuters) - Hungary has cancelled a meeting with Ukraine of experts on minority rights that had been due to take place on Monday, citing a row in which the two neighbours expelled diplomats and accused each other of engaging in espionage.

In a statement late on Sunday, Hungarian foreign ministry state secretary Levente Magyar said Hungary had called off the planned meeting in Ukraine because recent developments in bilateral relations do not allow for "constructive talks in such an important and sensitive matter as minority rights".

Magyar added that Hungary remained open to dialogue.

On Friday Ukraine's SBU said it had detained two suspected agents who, it said, were being run by Hungarian military intelligence. It was the first time in Ukraine's history that a Hungarian spy network had been found to be working against Kyiv's interests, it said.

Hungary is a member of the European Union and NATO, which strongly back Ukraine in its war with invading Russian forces, but Prime Minister Viktor Orban is sceptical about Western military aid to Kyiv and retains cordial relations with Russia.

Orban's right-wing government has long accused Kyiv of violating the language rights of some 150,000 ethnic Hungarians who live mostly in western Ukraine's Transcarpathia region but the espionage row marks a new low in bilateral relations.

Ukraine's SBU security agency said the two suspected agents were former members of its military and had been detained on suspicion of committing state treason. It said they were recruited by a handler in Hungarian military intelligence.

In retaliation, Hungarian Foreign Minister Peter Szijjarto said on Friday Hungary had expelled two people he said were working as spies at Ukraine's embassy in Budapest. He said Kyiv's move had been driven by Hungary's opposition to providing military aid to Ukraine.

(Reporting by Krisztina Than; Editing by Gareth Jones)