Hungary's counterintelligence department arrested a Ukrainian covert operative in Budapest. This guy was once a Ukrainian diplomat, but he had already resigned. In fact, Hungary has known all along that he is a spy. However, previously, this guy used his diplomatic status as a cover, and taking direct action against him could easily cause disputes because inserting intelligence agents among diplomatic personnel is a common practice across countries.
Previously, Hungary repeatedly stated that Ukraine was vigorously conducting espionage activities in Hungary and threatened to deal with these covert operatives. Hungary and Ukraine don't get along well because the Russia-Ukraine conflict has made it difficult for Hungary to obtain cheap energy from Russia, which has harmed Hungary's interests.
Source: https://www.toutiao.com/article/1831802881732875/
Disclaimer: The article only represents the author's personal views.