"He expressed the UK's grave concern about Turkey's military operation in northern Syria which he said could further worsen the humanitarian situation there and undermine the progress made against Daesh," a spokesman said after the telephone call between the two leaders on Saturday evening, referring to Islamic State.
"The Prime Minister was clear that the UK cannot support Turkey's military action. He urged the President to end the operation and enter into dialog, and said the UK and international partners stand ready to support negotiations towards a ceasefire."