ANKARA (Reuters) - Turkey may expand its planned purchase of Russian air defense systems if it cannot buy U.S. Patriots missile defense systems, and it will also look for alternatives if it cannot receive F-35 jets, Foreign Minister Mevlut Cavusoglu said on Wednesday.

He also said Turkey had not received a positive response from Washington over its proposal to form a joint working group to look into Ankara’s planned purchase of the Russian S-400 missile defense systems.