Russia’s most advanced fighter, which has undergone testing in Syria, is a direct competitor to the multi-role F-35 jet

The two leaders also toured an MC-21-300 narrow-body twin-engine jet passenger aircraft, which carried its maiden flight in May 2017. Developed by the Yakovlev Design Bureau and produced by its parent Irkut, a branch of the government-owned United Aircraft Corporation (UAC), the aircraft comes with a price tag of approximately $90 million and expected to be delivered to airlines starting from 2020.

Erdogan’s visit follows the U.S. decision last month to suspend Turkey’s ability to buy and help build the advanced F-35 stealth warplane in retaliation for defying Trump and taking delivery of a Russian S-400 air-defense system. The U.S. says the S-400 purchase is incompatible with Turkey’s role in NATO and the F-35 program because it may allow Russia to glean information about the fighter’s advanced technology.

Turkey had planned to buy about 100 F-35s and will have to seek alternatives if the U.S. maintains the ban. After a crisis in relations when Turkish jets shot down a Russian warplane near the Syrian border in 2015, Putin and Erdogan have strengthened economic and military ties in recent years as relations between Turkey and its NATO ally have strained.