Turkey has signed a deal for its first major weapons purchase from Moscow to buy S-400 missile defence systems, both sides announced Tuesday, in an accord that could trouble Ankara's Nato allies. The purchase of the surface-to-air missile defence batteries, Ankara's most significant deal with a non-Nato supplier, comes with Turkey in the throes of a crisis in relations with several Western states. "Signatures have been made for the purchase of S-400s from Russia. A deposit has also been paid as far as I know," Turkish President Recep Tayyip Erdogan said in comments published in several newspapers on Tuesday.

"Mr Putin (President Vladimir Putin) and myself are determined on this issue," he told Turkish journalists aboard his presidential jet returning from a trip to Kazakhstan. Moscow also confirmed the accord, with Vladimir Kozhin, Putin's adviser for military and technical cooperation, saying: "The contract has been signed and is being prepared for implementation." The purchase of the missile systems from a non-Nato supplier is raising concerns in the West over their technical compatibility with the alliance's equipment. The Pentagon has already sounded the alarm, saying bluntly that "generally it's a good idea" for Nato allies to buy inter-operable equipment.

Copyright Agence France-Presse, 2017