The Bulgarian Foreign Ministry said in a statement that "the diplomatic authorization to fly in the skies is of a temporary nature and falls within the framework of exceptions to EU sanctions imposed on it."
North Macedonia currently holds the rotating chairmanship of the Organization for Security and Cooperation in Europe (OSCE), which will hold its annual ministerial conference in the capital of the republic, Skopje, on November 30 and December 1.
In early November, North Macedonian Foreign Minister Bujar Osmani announced that Lavrov had asked to be allowed to attend the meeting.
At the organization's previous ministerial meeting in Poland last year, Warsaw refused to allow Lavrov to attend.
Warsaw's move at the time angered Moscow, which called the decision "unprecedented and provocative".
In October, Ukraine called for Russia's exclusion from the organization, which was founded in Europe to ease East-West tensions during the Cold War and to help its member states coordinate on issues such as human rights and arms control.
Russia has repeatedly accused the West of seeking to undermine and control the organization, noting that the body deviated from its founding principles.