Turkey is preparing to "clean" the Syrian side of the border of Islamic State jihadists after a Turkish border town came under repeated deadly rocket attacks, President Recep Tayyip Erdogan said on Thursday.

"We are doing all the necessary preparations to clean the other side of the border because of the problems in Kilis," Erdogan said amid persistent speculation of a possible Turkish cross-border ground operation. Around two dozen people have been killed in the Turkish border town of Kilis by rocket fire from IS jihadists since January.