NATO will convene Monday with the Middle East agenda to discuss the latest developments after the killing of Iranian top commander Qasem Soleimani in the U.S. airstrike.

Jens Stoltenberg, NATO secretary general, called for the meeting after speaking to allies, a NATO official told Anadolu Agency.

NATO ambassadors will meet at 3:00 p.m. local time (1400GMT), he added.

Soleimani's death marked a dramatic escalation in tensions between the U.S. and Iran, which have often been at a fever pitch since President Donald Trump chose in 2018 to unilaterally withdraw Washington from a 2015 nuclear pact world powers struck with Tehran.

Iranian Supreme Leader Ali Khamenei, who gave Soleimani the country's highest honor last year, vowed "severe retaliation" in response to his killing.

Soleimani was the long-time commander of Iran's Revolutionary Guards elite Quds Force, which is designated a terror group by the U.S. The group is estimated to have 20,000 members.