Turkey has signed a controversial deal with Russia to arm its forces with Russian S-400 anti-aircraft missiles. President Recep Tayyip Erdogan said a deposit had already been paid. The deal is thought to be worth $2.5bn (£1.9bn). Turkey has the second-largest army in Nato. The alliance reacted skeptically to the decision, saying the system was not compatible with its equipment. Turkey has been establishing closer links with Russia after its recent souring of ties with the US and Europe.
Mr Erdogan’s government objects to US military support for the YPG Syrian Kurdish rebels, who are linked to rebel Kurd’s in Turkey. Russia says the S-400 system has a range of 400km (248 miles) and can shoot down up to 80 targets simultaneously, aiming two missiles at each one. Russia deployed the S-400 at its air force base near Latakia in Syria in December 2015, after Turkish jets had shot down a Russian Su-24 warplane on the Syria-Turkey border. That incident caused a diplomatic rift between Russia and Turkey, but President Erdogan later patched up his quarrel with President Vladimir Putin.
A military adviser to Mr Putin, Vladimir Kozhin, said the S-400 contract with Turkey was “strictly compatible with our strategic interests”. “On that score, one can quite understand the reaction of some Western countries who are trying to put pressure on Turkey.” Relations between the two countries have deteriorated since Turkey arrested a Turkish-German journalist in February as part of a crackdown on political opponents in the country.