The US State Department on July 16 said it was working with Nato ally Turkey on the potential sale of a Raytheon Co Patriot missile defence system to render Ankara's planned purchase of a Russian-made S-400 system unnecessary.

Tina Kaidanow, Acting US Assistant Secretary of State for Political-Military Affairs, was reported by Reuters as telling journalists at the Farnborough Airshow in England that US officials were “trying to give the Turks an understanding of what we can do with respect to Patriot”.

Turkey passed on the Patriot system twice in its selection process, first choosing a Chinese system, then turning to the Russian S-400 system in 2017. US and Nato officials have repeatedly warned Ankara that the Russian system cannot be integrated into the Nato air and missile defence system, while its purchase would jeopardise Ankara’s acquisition of Lockheed Martin F-35 fighter jets. Turkey has so far angrily rejected calls from US senators for the scrapping of the planned S-400 acquisition.

Assistant Secretary of Defence Kevin Fahey, the Pentagon’s most senior official weapons buyer at the Farnborough event, reportedly told press at the show that “Turkey has had an interest in Patriot, so we’ve been working for a while how we can make that work.”

Kaidanow said Washington was worried that US allies purchasing Russian systems would support “some of the least good behaviour that we have seen from them [Russia] in various places including Europe but also elsewhere.” She said Washington wanted to ensure that systems acquired by US allies “remain supportive of the strategic relationship between us and our allies, in the case of Turkey that is Patriots.”