Kurdish fighters who came to Syria from around the Middle East to support Syrian Kurdish forces will leave if a total ceasefire is reached in the conflict with Turkey in northern Syria, the commander of Syrian Kurdish-led forces told Reuters on Thursday.

U.S. Senators Chris Van Hollen and Lindsey Graham have warned of bipartisan sanctions against Turkey if it rejects a ceasefire proposal from the U.S. and a plan by Syrian Democratic Forces (SDF) commander Mazlum Abdi to establish a demilitarized zone in Kobani.

Israel rejected Turkish accusations on Tuesday following Ankara’s condemnation of Israeli military actions in Syria, as Turkey escalates its own operations in the war-torn country. The rising tensions have deepened the rift between the two nations and sparked concerns over regional stability and the fate of U.

Replacing the dominant roles of Russia and Iran exerting influence over Syria, following the downfall of President Bashar al-Assad, Turkey and Israel are best positioned to divide up their respective roles on the territory of the shared neighbor.