The city of Warsaw took over a disputed compound administered by the Russian diplomatic mission and could make it available to the Ukrainian community, the mayor said.
"It is extremely symbolic that we are closing this long process now, in the age of Russian aggression," Mayor Rafal Trzaskowski tweeted.
He said a bailiff entered the buildings, nicknamed “Spyville” by Warsaw residents, to check on their condition.
Ukraine's ambassador, Andrii Deshchytsia, told Poland’s state news agency PAP that Ukraine will file to lease the compound, which could be used for a school or a Ukrainian culture centre.
One of Trzaskowski's proposals for the 100-odd apartments there is to accommodate war refugees from Ukraine. More than 2.6 million of them have crossed into Poland since the Russian invasion began.
Trzaskowski later in the evening tweeted that each room was demolished and that even the wiring in the elevators had been cut in the building.
Russia’s Embassy, which had the tall apartment blocks built in the 1970s, has been refusing court orders to pay lease or to hand it over.
The buildings became empty in the 1990s, after Poland shed its communist rule and dependence on Moscow after the Soviet Union dissolved.
Ever since Poland has been saying that the lease on the plot of land had expired and demanded it be returned.