A visible concentration of United States military aircraft at Sofia’s Vasil Levski Airport has sparked political debate and public speculation in Bulgaria. The buildup began in the middle of last week, when multiple large US Air Force planes were observed on the tarmac at both the civilian airport and the adjacent Vrazhdebna air base.

Reports circulated over the weekend suggesting that during specific nighttime windows, civilian flights would be suspended and the airport would operate exclusively for military traffic. Airport authorities rejected any link between the restrictions and the American aircraft, stating that temporary closures on February 23 and 24 were scheduled to allow routine repairs of runway shafts. The works were planned during hours with no regular commercial departures or arrivals. Earlier notices listed slightly different time slots, some of which partially overlapped with the final schedule, further fueling speculation. Officials stressed that the suspension applied to all flights without exception and was carried out in accordance with international aviation standards.

The Ministry of Defense confirmed that the aircraft belong to the US Air Force and described their presence as part of support for NATO’s Enhanced Vigilance Activities. The US Embassy in Sofia issued a similar statement, noting that the deployment was conducted under existing access, basing and overflight agreements. Acting Foreign Minister Nadezhda Neynski said the Foreign Ministry was reviewing the situation and would provide additional information when available. By the time of publication, responses to further inquiries had not been received.

The aircraft observed in Sofia include KC-135 Stratotanker refueling planes, designed to supply fuel mid-air to fighter jets and other aircraft. Cargo transports such as the C-17 Globemaster and C-130 Hercules have also been reported, capable of moving equipment, personnel and paratroopers. A variant of the Boeing 737 used by the US Air Force, adaptable for troop transport or airborne command functions, has likewise been mentioned. The KC-135 fleet, developed from the Boeing 367-80 prototype and in service since the late 1950s, has undergone multiple modernization programs to improve efficiency, communications and navigation systems.

Similar aircraft have been tracked at other European locations, including bases in Spain, Italy, Greece and the Azores. In southern Spain, local media reported that a KC-46 Pegasus tanker sustained minor damage that temporarily disrupted activity at Morón air base near Seville. According to monitoring data cited by international media, dozens of heavy transport aircraft and refueling tankers have been spotted across Europe in recent days. Analysts note that the presence of “flying tankers” is significant because they extend the operational range of combat aircraft without requiring deployment in countries bordering Iran.

The developments coincide with a broader US military buildup near the Middle East. The aircraft carrier Abraham Lincoln and its strike group were dispatched to the Arabian Sea, while the USS Gerald Ford recently entered the Mediterranean through Gibraltar and continued eastward. Additional US destroyers are operating in the Mediterranean, the Red Sea and near Bahrain. Fighter aircraft, including F-22s temporarily deployed to the United Kingdom, have been repositioned in Europe and the Middle East, alongside assets stationed at Diego Garcia in the Indian Ocean. Reports indicate that more than 100 US fighter jets and bombers, including F-22, F-35, F-15, F-18 and B-2 aircraft, are currently in operational proximity to Iran. Airborne early warning aircraft such as the E-3 Sentry have also been identified in the region.

Speculation about a possible US strike against Iran has intensified amid these movements. American media describe the current deployment as the largest regional buildup in years, though US officials emphasize that no final political decision has been announced. Diplomatic contacts between Washington and Tehran have continued, including indirect discussions in Geneva focused on Iran’s nuclear program, but no breakthrough has been reported.

Reactions have extended beyond Bulgaria. Russian Foreign Minister Sergei Lavrov warned that military escalation would carry serious risks, while Iranian President Masoud Pezeshkian reiterated that Tehran does not seek conflict but will defend its stated positions. Washington maintains that it aims to prevent Iran from acquiring nuclear weapons, whereas Iranian authorities insist their nuclear activities are civilian in nature and have signaled readiness for limitations in exchange for sanctions relief.

Against this international backdrop, the concentration of US aircraft in Sofia, though officially described as linked to NATO training, has become part of a wider picture of shifting military posture across Europe and the Middle East.