U.S. Defense Secretary Jim Mattis said that the the United States is in talks with Turkey regarding Syria's Manbij, Anadolu Agency reported Friday evening.

Mattis also added that it was not the right time to discuss the matter publicly. He said that speaking about Manbij publicly "could make the situation more difficult, in terms of domestic audiences that have got to deal with their [countries'] own understandable positions."

"It's how do you balance the competing interests. I can just tell you it's an active discussion right now with our ally, Turkey," he added.

While Turkey seeks to expand its ongoing Operation Olive Branch to clear terrorists off of its borders, U.S. General Joseph Votel previously said that the United States would not withdraw troops from Syria's People's Protection Units (YPG)-held town of Manbij.

Turkish officials have consistently noted that Operation Olive Branch will continue into Manbij and have criticized the U.S. for not keeping its promises, in terms of the pledge given by the U.S. that local councils would run the cities after they were liberated, but the PYD/PKK took control in northern Syria.

Previously, the U.S. administration under former President Barack Obama had promised Turkey that the YPG terrorists would move east of the Euphrates. However, despite warnings from Ankara, the promises were not kept, and the YPG did not move east of the Euphrates.

The YPG's ultimate aim is to establish an autonomous region in northern Syria by connecting the northwestern Afrin canton to the Kobani and Jazeera cantons in the northeast, which is considered a "terror corridor" by the Turkish government.

As a result of the broken promises by the U.S., Turkey also shifted its position and vowed to clear all terrorists from northern Syria, including Manbij and the eastern parts of the Euphrates.

Operation Olive Branch was launched on Jan. 20 to clear YPG terrorists that have been harassing Turkey's borders for a long time.