ISTANBUL (Reuters) - Turkey’s defense minister on Friday pledged to wage a campaign against a U.S.-backed Syrian Kurdish militia, sharpening focus on a potential conflict the United States has sought to prevent.

FILE PHOTO: Turkey's Chief of the General Staff Hulusi Akar is seen during the EFES-2018 Military Exercise near the Aegean port city of Izmir, Turkey May 10, 2018. REUTERS/Osman Orsal

The comments from Hulusi Akar, on an unannounced visit to inspect troops stationed near the Syrian border directly opposite territory held by the U.S.-backed Kurdish YPG, appeared to be aimed at both Washington and its Kurdish allies.

Turkey and the United States, although NATO allies, are deeply divided over the implementation of President Donald Trump’s plan to bring home about 2,000 troops stationed in Syria. The plan hinges on Turkish cooperation to secure a swathe of northeast Syria as the United States departs.

While the pull-out has been clouded by mixed messages from both Trump and his administration, on Friday the U.S.-led coalition against Islamic State began the process of withdrawing, a spokesman said.

Trump’s national security adviser, John Bolton, this week tried to make the case for guarantees that Turkey would not harm the YPG after the withdrawal. That earned a stiff rebuke from President Tayyip Erdogan. Turkey considers the YPG a terrorist organization and sees Washington’s support for it against Islamic State as a betrayal.

“When the time and place comes the terrorists here will be buried in the ditches they have dug, as was done in previous operations,” Akar said in a speech to military personnel at a brigade command center in the province of Sanliurfa, referring to two other cross-border campaigns that Turkey has carried out in Syria.

Turkey views the YPG as an extension of the outlawed Kurdistan Workers Party (PKK), which has waged a three-decade insurgency in Turkey’s largely Kurdish southeast. The Kurdish groups that control a vast swathe of northern Syria have now turned to Moscow and Damascus in the hope of striking a political deal that will stave off Turkey and shield their autonomy in the north.

Ankara has repeatedly expressed frustration over a deal with the United States for the withdrawal of the YPG from the city of Manbij, just west of the Euphrates river.

“Before us we have Manbij on one side and the east of the Euphrates on the other,” Akar said, underscoring the scale of a potential operation. “Important preparations and planning have been made in connection with this. Our preparations are continuing intensively.”

Turkey’s planned military operation against a Kurdish militia in Syria does not depend on an American withdrawal from the region, Ankara said on Thursday.