Turkey renewed air strikes on Islamic State sites in Syria on Friday, Sept. 2 extending operations along a 90-km (56-mile) corridor near the Turkish border which Ankara says it is clearing of jihadists and protecting from Kurdish militia expansion, according to Reuters.

Turkey's 10-day-old offensive, its first major incursion into Syria since the war started five years ago, has alarmed the West.

The United States has voiced concerns about Turkish strikes on Kurdish-aligned groups that Washington has backed in its battle against Islamic State. Germany said it did not want to see a lasting Turkish presence in an already tangled conflict.

Turkey has said it has no plans to stay in Syria and simply aims to protect its frontier from the militant group and the Kurdish YPG militia, which it sees as an extension of the outlawed Kurdish PKK group fighting an insurgency on Turkish soil.

"Nobody can expect us to allow a terror corridor on our southern border," President Tayyip Erdogan told a news conference.

Washington says Turkish action aimed at the YPG, part of the U.S.-backed Syrian Democratic Forces (SDF) coalition, risked undermining the broader goal of ridding Syria of Islamic State, which has attacked Western and Turkish targets.

Turkish forces and their Syrian rebel allies began the Aug. 24 offensive by seizing Jarablus, a Syrian frontier town, from Islamic State, before turning their sights on what the army said were YPG positions. The YPG denied they were there.

In an interview with Reuters on Friday, Deputy Prime Minister Numan Kurtulmus called on the United States to put more pressure on the YPG to return east of the Euphrates river, a move that Turkey hopes would keep the Kurdish militia in check.