Prague/Moscow - The expected has happened. Russia retaliated and expeled two Czech diplomats from the Moscow-based Czech embassy, as reported by Interfax press agency Tuesday.

"This unfriendly act of the Czech Republic which declared two of our diplomats as persona non-grata, naturally could not be left without a response," said an unidentified official from the Russian Foreign Affairs Ministry.

The Czech Republic expeled two Russian diplomats earlier on Monday due to suspicion they were spying for Russia's secret services.

The Russian expelled diplomats are a military attaché from the Russian embassy and another Russian diplomat that was advised not to return from his holidays to the Czech Republic, as first reported by idnes news server on Monday.

"It is surprising that this information became public knowledge despite the fact that the Czech side itself proposed not to allow any leak," the Russian ministry official told Interfax.

"This is another provocation," Russian Foreign Minister Sergei Lavrov told journalists on Monday, failing to specify what kind of provocation he had in mind.

Russia, the United States and Great Britain share a history of mutual diplomat expulsion. The latest case is two Canadian diplomats who were ordered to leave the country by the Russian authorities in May this year.

Interestingly, none of the foreign ministries has made any official statement. They both send messages to each other via local media.