The US State Department called the closure of the sky for the aircraft with Lavrov "sovereign decision" of the countries

“These were sovereign decisions regarding the airspace of these three sovereign states,” said US State Department spokesman Ned Price during a briefing.

Earlier, the official representative of the Russian Foreign Ministry, Maria Zakharova, confirmed that a number of European countries closed their airspace to Lavrov's plane, which was heading to Serbia.

Russian Ambassador to Belgrade Alexander Botsan-Kharchenko said that the planned visit of the head of the Russian Foreign Ministry to Serbia was postponed. 

Lavrov called "inconceivable" the decision of a number of European countries not to let his plane through to Serbia.