"We are currently reviewing options for the Joint Coordination Center with our Turkish military counterparts," Defense Department spokesman Commander Sean Robertson told AFP.

"The security mechanism will be implemented in stages," Robertson said.

"The United States is prepared to begin implementing some activities rapidly as we continue discussions with Turkey."

According to terms of the hard-won agreement between Ankara and Washington reached last week, authorities will use the coordination center, located in Turkey, to organize a safe zone in northern Syria.

The goal of the zone is to create a buffer between the Turkish border and areas controlled by the Kurdish People's Protection Units (YPG) -- which is supported by the US but is classified as a terrorist organization by Turkey.

But retired general Joseph Votel, the former chief of US troops in the Middle East, has publicly opposed Ankara's control of such a zone.

In an opinion piece published on The National Interest's website Monday, Votel, who headed the US Central Command until last March, warned that he thinks a Syrian security zone controlled by Turkey would "create more problems for all parties involved."

"Safe zones are generally established to protect people in conflict zones and are usually designed to be neutral, demilitarized, and focused on humanitarian purposes," Votel wrote in the article with George Washington University Turkey expert Gonul Tol.

"Imposing a twenty-mile-deep (30 kilometer) safe zone east of the Euphrates would have the opposite effect -- likely displacing more than 90 percent of the Syrian Kurdish population, exacerbating what is already an extremely challenging humanitarian situation, and creating an environment for increased conflict," they wrote.

Syrian Kurds -- who have played a key role in the fight against the Islamic State jihadist group -- have established an autonomous region in northeast Syria amid the country's brutal civil war.

But as the fight against IS winds down in the region, the prospect of a US military withdrawal stoked Kurdish fears of a long-threatened Turkish attack.

Turkey has already carried out two cross-border offensives into Syria in 2016 and 2018, the second of which saw it and allied Syrian rebels overrun the Kurdish enclave of Afrin in the northwest.