He called it a "difficult situation."
"They get the S-400 ... I do not blame Turkey, because there are many circumstances and other problems that appeared during the Obama administration," RIA Novosti quoted Trump.
At the same time, he noted that Washington could “easily sell to other countries” F-35 fighters intended for sale to Ankara.
Earlier, the Turkish leader Recep Tayyip Erdogan said that he hoped for US sanity regarding the supply of C-400 to Ankara.
Expert Edward Lozansky commented on the NSN's likelihood of imposing sanctions against third countries because of the C-400.