Estonia on May 5 said that a Russian passenger plane carrying Foreign Minister Sergei Lavrov to neighboring Finland briefly violated Estonian airspace this week.
The incident on May 3 was the first alleged airpace violation of Estonia, a NATO member, this year after the Baltic nation reported seven similar air intrusions last year.
Russia's Foreign Ministry denied any intrusion, saying Lavrov's plane followed a previously agreed route and did not receive any warnings that it strayed from it.
But Estonia's military said the plane hadn't filed a flight plan and made no radio contact.
Estonian media said the Rossiya Airlines plane briefly traveled over northern Estonia near Vaindloo island, a place where Russian military planes previously have intruded in the past.
Estonia's Foreign Ministry sent a note on the incident to Russia's embassy in Tallinn.
Most Estonian airspace intrusions have been caused by Russian military aircraft flying in the narrow air corridor from Russia's Baltic Sea enclave of Kaliningrad to the Russian city of St. Petersburg.
In the past year, NATO and Russia have discussed reducing the risk of air accidents in the crowded skies over the Baltic Sea by agreeing on common practices and using aircraft transponders.
Based on reporting by AP and TASS