Russia stated that Poland impounding a school run by the Russian Embassy in Warsaw on Saturday was a "blatant violation" of international agreements, warning of "harsh" repercussions.

"We regard this as yet another hostile act by the Polish authorities and a blatant violation of the Vienna Convention of 1961," the Russian Foreign Ministry said. 

It "goes beyond the framework of civilized interstate communication and will not remain without our harsh reaction and consequences for Polish authorities and Poland's interests in Russia," the Ministry added. 

This comes after Poland said it had seized a high school building near Moscow's Embassy in Warsaw meant for the children of diplomats.

It is worth noting that the dispute over the 1970s multi-story building, nicknamed the "spy nest" by Warsaw citizens, has been going on for a year.

"This building belongs to the Warsaw City Hall," Polish Foreign Ministry Spokesperson Lukasz Jasina said, as quoted by AFP, stressing that the move followed a bailiff's order.

Poland claims there is a huge disparity in the number of diplomatic buildings each had in the other country.

On his account, Moscow's envoy, Sergei Andreyev, said as quoted by RIA Novosti news agency that "this is an illegal act. An intrusion on a diplomatic facility." 

Andreyev said this was a "violation of Vienna's convention of diplomatic relations." 

"Of course, there will be a reaction," Andreyev said, stressing that he did not want to give further details and that a decision will be made in Moscow. 

"We consider the school by the embassy to be part of our diplomatic mission," he said, adding teachers and staff lived on the territory of the building.  

Andreyev concluded by affirming that the school will continue to work in a different part of the Russian embassy's premises. "Our priority is ensuring the safety and the interests of our employees and their families," he stated.

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