ANKARA – Turkish President Tayyip Erdogan has said that the purchase ofS-400 defense systems from Russia is a done deal and Ankara would alsojointly produce S-500 defense systems with Moscow.

In a televised question and answer session with university students inIstanbul he said the U.S. officials have called Turkey’s planned purchaseof S-400 missile defense system deeply problematic.

He said it would risk Ankara’s partnership in the joint strike fighter F-35program because it would compromise the jets, made by Lockheed Martin Corp.