Russia summoned the Belgian ambassador on Friday in a spat over Moscow's claim that Belgian jets killed six civilians near Syria's Aleppo, the foreign ministry said.
Foreign ministry spokeswoman Maria Zakharova confirmed to AFP that Belgian ambassador Alex Van Meeuwen had gone to the ministry earlier Friday in response to a summons.
The Russian defense ministry on Wednesday said that six people were killed and four injured by airstrikes in the Aleppo region while two Belgian F-16 planes were present in the region.
Belgium has denied the claim and demanded that Russia formally withdraw it. On Wednesday, it summoned the Russian ambassador to Brussels to protest.
Belgium said that a map with a flight path on it provided by Moscow showed the aircraft identification numbers did not belong to the Belgian Air Force.
However Russian defense minister spokesman Igor Konashenkov said Thursday that Moscow was confident of its information.
"Russia has effective air defense capabilities, allowing it to carry out 24-hour monitoring of air activity practically over the whole territory of Syria and beyond its limits," he said.
Belgium announced in May that it would extend its F-16 air strikes against Islamic State jihadists in Iraq into Syria after deadly IS-claimed bomb attacks in Brussels in March.