Secretary of State Mike Pompeo isn’t interested in forming a “technical working group” to discuss whether Turkey’s purchase of major Russian weaponry could endanger Western militaries.

Turkey has sparked an international uproar by insisting on the purchase of Russian S-400 anti-aircraft missile defense systems, which the NATO ally wants to deploy alongside Western military systems. Turkish Foreign Minister Mevlüt Çavuşoğlu dismissed U.S. assessments that the deal would help Russia learn how to target the American-made F-35 and called for a working group to discuss the issue, but Pompeo’s team thinks that would be a waste of time.