Turkey says it will deal with the YPG on its own terms

Turkey would act "without asking anyone" if it comes under attack from the US-backed YPG in Syria, Turkish President Recep Tayyip Erdogan told his US counterpart during their meeting in Washington DC this week, Turkish official sources said.

US President Donald Trump recently approved the supply of arms to the PKK-linked YPG for its assault on Raqqa, the de-facto Daesh capital in Syria.

"We clearly told them this, 'if there is any sort of attack from the YPG and PYD against Turkey, we will implement the rules of engagement without asking anyone'," Erdogan was quoted as saying by the Daily Sabah newspaper.

The YPG is the military wing of the PYD, a Syrian affiliate of the PKK, which Turkey, the US and EU list as a terrorist organisation. The US considers the YPG a valuable ally in its fight against Daesh.

During his meeting with the US president, Erdogan underlined Turkey's concerns about the YPG. He told Turkish reporters that, as the US had made its decision on Raqqa, Turkey would not participate given YPG involvement.

"We told them ... we do not regard your cooperation with a terrorist group in Raqqa as healthy," Erdogan said.

The Turkish president added that he expected Turkey to continue to play a role in Syria.

"I believe they will knock on our door on the subject of Syria," he told reporters.

US-backed SDF advance

US-backed Syrian Democratic Forces (SDF), a Kurdish and Arab grouping which is dominated by the YPG, have seized 350 square kilometres around Raqqa, a spokesperson for the US-led coalition said on Wednesday.

Some 3,000 to 4,000 Daesh militants are thought to be holed up in the city, Colonel Ryan Dillon, a spokesman for the coalition, said.

The SDF has been closing in on Raqqa since November in a multi-phased offensive backed by the US-led coalition that is also fighting Daesh in Iraq.

"In the last week, the SDF have tightened their noose around ISIS [Daesh] in the northern and eastern and western part of Raqqa," Dillon said.

Turkey wants US anti-Daesh envoy to be replaced

In a sign of Turkey's concern over US support for what it considers a terrorist organisation, Turkey's Foreign Minister Mevlut Cavusoglu on Thursday called on Washington DC to replace its anti-Daesh envoy Brett McGurk because of his support for the PKK and PYD in Syria.

"Brett McGurk is definitely giving clear support to the PKK and YPG," Cavusoglu said. "It will be beneficial if this person is replaced."

McGurk was appointed as a presidential envoy for the anti-Daesh coalition by ex-president Barack Obama in October 2015.

Three months later, McGurk was pictured alongside PKK/PYD militants in northern Syria, angering Ankara.