Poland says there is a big disparity in the number of diplomatic buildings each has in the other's country.
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Russia has reacted angrily after Warsaw city authorities closed down their secondary school which had been run by the Russian embassy in Poland.
Moscow denounced it as "blatant violation" of international agreements and warned of "harsh" consequences.
Poland says there is a big disparity in the number of diplomatic buildings each has in the other's country.
On Saturday the school was starting to be emptied by Russian staff.
Former Russian President Dmitry Medvedev lashed out on Twitter, saying, that there was no point in maintaining diplomatic relations with Poland anymore.
"The Ukraine is full of Polish mercenaries, who should be ruthlessly exterminated like stinky rats," he added.
A Polish foreign ministry spokesman said the building now belongs to Warsaw City Hall.