NATO Secretary General Mark Rutte reaffirmed the alliance’s support for Bulgaria and its readiness to respond to any threat to NATO member states during a phone call with Bulgarian Prime Minister Rumen Radev on Thursday, according to Bulgaria’s state news agency BTA.

Radev and Rutte discussed the security environment in Europe, focusing on the potential risk of aggressive action by Iran, according to a statement from Bulgaria’s Council of Ministers.

Rutte confirmed NATO’s full support and the readiness of the alliance’s defense forces and capabilities in the region to respond to and neutralize any threat to NATO member states.

He also pointed to the recent successful interception of ballistic missiles heading toward Türkiye as a demonstration of NATO’s readiness to provide protection.

Any attack on a NATO member state will be treated as an attack against the alliance, with measures under the North Atlantic Treaty to follow, according to the statement.

The conversation followed a Financial Times report that Iranian forces had assessed striking US military assets in Bulgaria, according to two people close to the Iranian regime.

Bulgarian authorities reportedly increased security at Bezmer Air Base, which had been approved for use by US refueling aircraft, but said there was no direct threat to national security.