US President-elect Donald Trump said on Monday that Turkey will "hold the key" to what happens in Syria, where rebels backed by Ankara toppled the government of Bashar al-Assad earlier this month, Reuters reports.

By supporting the rebels, "Turkey did an unfriendly takeover without a lot of lives being lost," Trump told a press conference at his residence in Palm Beach, Florida.

"Right now, Syria has a lot of, you know, there's a lot of indefinites ... I think Turkey is going to hold the key to Syria," Trump said.