Margarita Robles, Spain’s defence minister, has confirmed that the country is closing its airspace to US planes carrying out missions against Iran.

The decision comes as a result of Spanish Prime Minister Pedro Sanchez’s consistent opposition to the war launched by US-Israeli strikes on February 28. Sanchez has emerged as one of the highest-profile Western leaders to speak out against the conflict, which has engulfed the entire Middle East. His stance has infuriated Spain’s traditional NATO ally, the United States.

The closure of Spanish airspace is expected to “complicate” US military operations, forcing bombers to change their routes and logistics on their way to the Middle East. The transit or landing of planes will only be allowed in case of an emergency, according to reports by El Pais daily.

Spanish Prime Minister Sanchez has faced pressure from the US President Donald Trump over his stance on NATO defence spending. However, Spain had already sparked Trump’s anger by refusing to agree to raise spending to five percent of member states’ GDP as demanded by the US president.