Russia has suspended its mission to Nato, its foreign minister said on Monday.
Sergey Lavrov said the move was in response to last week’s expulsion from the military alliance of eight members of Russia’s mission.
Nato alleged that they had been working secretly as intelligence officers.
The group of 30 nations headed by Jens Stoltenberg halved the size of Moscow’s team from 20 to 10.
The Russian mission is not based at Nato’s headquarters in Brussels but in a leafy neighbourhood in the south of the Belgian capital.
Mr Lavrov also announced that Nato’s military liaison and information offices in Moscow would close.
“As a result of Nato’s deliberate moves, we have practically no conditions for elementary diplomatic work and in response to Nato’s actions we suspend the work of our permanent mission to Nato, including the work of the chief military envoy, probably from November 1. Or it may take several more days,” Mr Lavrov said.
Relations between Nato and Russia have been increasingly strained since Moscow’s annexation of Ukraine’s Crimean peninsula in 2014 and by the continuing conflict in the region.
Nato suspended practical co-operation with Russia but opted to keep channels open for high-level meetings and military liaison.
The Nato-Russia Council now meets only sporadically.
The organisation and Russia are also at odds over Moscow’s nuclear missile development, aerial intrusions into Nato airspace and the 'buzzing' of allied ships by fighter planes.
At a summit in June, Nato leaders agreed there could be no return to "business as usual" with Moscow until it complies with international law.
In April, Ukraine's President Volodymyr Zelensky piled pressure on Nato to speed up its path to membership as Moscow amassed its military presence on the Russia-Ukraine border.
Mr Zelensky said joining the international alliance was "the only way to end the war" in eastern Europe.
A spokesman for Russian President Vladimir Putin reacted by warning that Ukraine joining the group would “further aggravate the situation”.
