Estonia Triggers NATO Article 4 After MiG-31 Breach

Estonia has called for alliance consultations after a brief airspace incursion by three Russian MiG-31 fighters on September 19, 2025.

Tallinn said the three MiG-31s — a Soviet-era interceptor still operated by Russia — entered Estonian airspace over the Gulf of Finland and remained inside for roughly 12 minutes on September 19, 2025. The incident prompted Estonia to invoke NATO Article 4, asking North Atlantic Treaty Organization (NATO) members to consult on a perceived security threat.

NATO Article 4: what Estonia asked for

Article 4 allows any ally to request consultations when it believes its territorial integrity or security is threatened. Estonia described the incursion as a brazen breach, lodged formal diplomatic protests with Moscow, and alerted allied capitals. The jets returned to Russian territory after the short transit; no damage or engagements were reported.

Expectations inside Tallinn and Brussels are that NATO will convene urgent talks to review air policing measures, situational awareness over the Baltic region, and how to deter similar moves. Estonian air surveillance and NATO Baltic air policing assets have been more active in recent years as regional tensions have risen.

NATO Article 4 consultations were triggered by the 12-minute MiG-31 airspace incursion over the Gulf of Finland.

Diplomatic fallout is already underway: Estonia has protested through its foreign ministry and allied governments have expressed concern. While the episode did not escalate into a kinetic confrontation, it underscores the strategic sensitivity of the Baltic airspace and the role allied consultation plays in de-escalation.