Turkish President Recep Tayyip Erdogan has dismissed US calls for a ceasefire in northern Syria and said that he's not worried about American-imposed sanctions, or the advancement of Russian-backed Syrian forces toward the Turkish border.

Speaking to journalists travelling on his presidential plane following a visit to Azerbaijan Tuesday, Erdogan said a ceasefire was off the table. “Declare a ceasefire, they say. We will never declare a ceasefire,” Erdogan said. “We do not sit at the table with terrorist organizations.”

Erdogan's comments come as Russian-backed Syrian regime troops on Tuesday gained control of the town of Manbij and surrounding areas, until recently an active US military outpost.

Russia has stepped up its role in the Syrian conflict by deploying military police to the country's north — filling a vacuum left by the withdrawal of US troops from the area.

Russian units are patrolling a contact line between Syrian and Turkish forces, according to a statement by Russia's Defense Ministry. On Tuesday, Russia's presidential envoy on Syria, Alexander Lavrentiev, told state news agency TASS that Moscow “won't allow” clashes between Turkish and Syrian forces on the ground.

After Turkey launched a long-threatened offensive across the border into Kurdish-controlled northeastern Syria last week, local Syrian Kurdish leaders struck a deal with Syria's government in Damascus to enforce the border.

The Syrian Democratic Forces (SDF) who operate in the area are led by the Kurdish People's Protection Units (YPG), which Turkey considers a terrorist organization affiliated with the separatist Kurdistan Workers’ Party (PKK). The SDF, however, are US allies that were considered instrumental in the fight against ISIS in northern Syria.

Turkey's offensive, called the Peace Spring Operation, is aimed at clearing Kurdish forces away from its border area and resettling 2 million Syrian refugees currently hosted in Turkey into a 30 kilometre (18.6 miles) “safe zone” along the border.

On Tuesday, the Trump administration said it was dispatching Vice President Mike Pence, Secretary of State Mike Pompeo and national security adviser Robert O'Brien as part of a delegation departing to Ankara Wednesday, to broker a deal to stop the Turkish military operation in Syria.

The delegation's planned departure comes after President Donald Trump announced sanctions against Turkey and threatened to “destroy” the country's economy if it does not halt its incursion.

On Monday, Trump tweeted a statement saying he would soon authorize via executive order new sanctions on current and former Turkish officials. He said he'd also reimpose heavy duties on Turkish steel and cut off trade talks.

It marks an attempt by the White House to adopt a firmer stance after facing harsh criticism from Republican lawmakers and senior national security veterans for withdrawing US troops from northern Syria, paving the way for Turkey's military offensive.
But Erdogan told reporters onboard the presidential plane Tuesday that his government is “not worried” about any US sanctions.

“They are pressuring us to stop the operation (in northern Syria). They are announcing sanctions. Our goal is clear. We are not worried about any sanctions,” he said.

Erdogan not concerned about Syrian forces

According to the Russian Defense Ministry, Syrian government forces have taken control of two areas in northern Syria on Tuesday — more than 1,000 square kilometres around the town of Manbij and an area in Raqqa around the town of Tabqa.
Erdogan said Tuesday that Syrian regime forces entering Manbij was “not very negative for me” so long as Kurdish “terrorists” are cleared from the region.

“It's their lands after all. But what is important to me is that the terrorist organization does not remain there,” he said.

The Turkish president said he told Putin, a key ally of the Syrian government, that “if you are clearing Manbij of terrorist organizations, then go ahead, you or the regime can provide all the logistics. But if you are not going to do this, the people there are telling us to save them.”

Erdogan also told reporters that the latest delivery of a Russian-made S-400 missile defence system — which Washington opposes Ankara buying — will arrive in November or December.

The first delivery of components arrived in July and Erdogan's comments are likely to further rile up US officials, who have threatened to level sanctions against Turkey if the system ever became operational.

The State Department had repeatedly warned that “Turkey will face very real and very negative consequences if it completes the delivery of the S-400,” as spokesperson Morgan Ortagus said at the end of May.