Kurdish fighters have been America's partners on the ground in the war against IS in Syria.
The US Secretary of State Mike Pompeo is said to be optimistic that a “good outcome” could be reached between Turkey and Syrian Kurdish groups, after speaking to the Turkish Foreign Minister.
Kurdish-led groups who control parts of northern Syria fear an attack from Turkey in the wake of President Donald Trump’s decision to withdraw troops from Syria.
Mr Pompeo, who is on a tour of the region, has sought to reassure the Kurds that they will be safe after US troops withdraw from the country.
"These have been folks that have fought with us and it's important that we do everything we can to ensure that those folks that fought with us are protected".
He said of the Kurds earlier this week, while visiting Irbil, the capital of Iraq's semi-autonomous Kurdistan region, after talks in Baghdad.
The US-led military confirmed it has begun the process of withdrawing from Syria.
An official said the equipment withdrawal is underway and an unspecified number of additional US troops have been moved into Syria to assist with the withdrawal process, including to provide additional security.
The British-based Syrian Observatory for Human Rights, which monitors the conflict in Syria through a network of activists on the ground, said the withdrawal began on Thursday night.