Turkey on Monday warned the United States it was time to either make or break ties between the NATO allies that have strained badly over the Turkish operation in Syria, days ahead of key talks with Washington's top diplomat.

 

US Secretary of State Rex Tillerson is due in Ankara later this week for talks aimed at finding a way forward as Washington expresses severe alarm over the campaign against Kurdish militia.

 

"Our relations are at a very critical point. They will either be fixed or these ties will be completely damaged," Turkish Foreign Minister Mevlut Cavusoglu said in televised comments in Istanbul.

 

Ankara last month launched a military operation against the Kurdish People's Protection Units (YPG) militia in the western enclave of Afrin in northern Syria.

 

While Turkey views the YPG as a "terrorist" offshoot of the outlawed Kurdistan Workers' Party (PKK), the US has been working closely with the militia against the Islamic State extremist group in Syria and giving it weapons.

 

Turkey is also angry Washington has failed to extradite Pennsylvania-based Muslim preacher Fethullah Gulen, who it accuses of ordering the 2016 attempted overthrow of President Recep Tayyip Erdogan.

 

The US has called for Turkey to show restraint in its Afrin operation. But Ankara has warned the US to remove its troops from the YPG-held Manbij town as it threatens to extend the operation towards the town east of Afrin.

 

The US has more than 2,000 special forces and support troops inside Syria, mainly east of the Euphrates in an area also controlled by the YPG but separate from Afrin, which is west of the river.

 

Cavusoglu called on the US to "do what is necessary in Manbij".

 

He added the talks with Tillerson would discuss rebuilding the "broken trust", accusing Washington of making "serious mistakes" on Gulen and the YPG.

 

"We have open and clear expectations which we have repeatedly shared," Cavusoglu said. "We do not want promises, we want concrete steps to be taken."

 

US National Security Advisor H.R. McMaster was in Istanbul this weekend to meet Erdogan's spokesman and foreign policy advisor Ibrahim Kalin, the Turkish presidency said on Sunday.

 

The presidency said they reaffirmed "long-term strategic partnership relations between Turkey and the US" and "ways of developing a joint fight against terrorism in all its forms".