Turkey accused Barack Obama of arming “terrorists” in a Kurdish militant group in Syria which it has blamed for a deadly car bombing which claimed at least 28 lives on Wednesday.
The Turkish President Recep Tayyip Erdoğan has accused the US-supported Kurdish rebel group YPG of carrying out the attack in Ankara.
America has supported the YPG fighters - linked to the political PYD group - in their fight against Islamic State in Syria but Turkey insists they are terrorists.
Erdoğan said he tell Mr Obama that plane loads of weapons sent from the US had aided Kurdish group - and had also ended up in the hands of Isis.
"Three plane loads arrived, half of them ended up in the hands of Daesh (Islamic State), and half of them in the hands of the PYD," he said