Turkish ground troops have entered a Kurdish-held enclave in northern Syria and are advancing with Turkish-backed Syrian opposition forces, according to the country’s state-run news agency.

Anadolu Agency said the troops pushed into Afrin on Sunday, a day after Turkish jets pounded Syrian Kurdish targets in the region.

The Turkish military says its offensive, named operation Olive Branch, aims to rid the region of the Kurdish People’s Protection Units, or YPG.

Turkey considers the YPG a terror organisation because of its affiliation to Kurdish rebels fighting in south-eastern Turkey, and had been threatening to attack Afrin for weeks.

Turkish President Recep Tayyip Erdogan has promised to expand the operation to other Kurdish regions.

The YPG is a key US ally in the war against the Islamic State group.