Turkey will soon start combating Islamic State group militants inside northern Syria, its foreign minister vowed Wednesday as he met US Secretary of State John Kerry in Malaysia.

"Now we are training and equipping the moderate (Syrian) opposition together with the United States, and we will also start our fight against Daesh very effectively soon," Foreign Minister Mevlut Cavusoglu told reporters at the start of the meeting with Kerry, using the Arab acronym for the militant group.

"Then the ground will be safer for the moderate opposition that are fighting Daesh on the ground," he added.