Trump said Wednesday he "will absolutely do safe zones in Syria" for refugees fleeing violence. According to a document seen by Reuters, Trump is expected to order the Pentagon and the State Department in the coming days to craft such a plan.

"We have seen the US President's request for conducting a study. What's important is the results of this study and what kind of recommendation will come out," Muftuoglu told reporters at a briefing in Ankara.

He also said some elements in Syria may be frustrated by progress made at peace talks in the Kazakh capital Astana and may seek to disrupt a ceasefire.

It was incumbent on guarantor countries, which include Turkey, Russia and Iran, to prevent that from happening, Muftuoglu said.