According to sources, the Russian-Turkish cooperation on military software and technology exchange discussed during Russian President Vladimir Putin's visit to Turkey on April 3 may also include the delivery of Sukhoi jets, namely the Su-57, a direct competitor of the F-35, the Yeni Safak newspaper reported.
Russia and Turkey signed a loan agreement last December to supply S-400 air defense systems to Ankara. The deal triggered disagreements between Turkey and the United States, with the latter threatening to impose sanctions against Ankara, as Washington believes that the weapon was incompatible with NATO defenses. On Friday, Putin criticized the United States for trying to force Turkey out of the deal with Russia.
Russia's Su-57 fifth-generation fighter jet, formerly known as Prospective Airborne Complex of Frontline Aviation (PAK FA), is a single-seat, twin-engine multirole "stealth" aircraft designed for air superiority and attack roles. It is equipped with an advanced avionics system and airborne active phased array radar as well as with a variety of high-precision weaponry. The jet carried out its maiden flight in 2010 and is still being tested by the military.