Turkey on Monday vowed it would not be intimidated by US President Donald Trump's threats of economic devastation if Ankara attacks Kurdish forces as American troops withdraw.
Trump's threat came after Ankara repeatedly threatened a new cross-border operation against the Kurdish People's Protection Units (YPG), which have been working closely with the United States in the war on Islamic State (IS) extremists.
US support to the YPG has been a major source of tension between the NATO allies.
"We have said repeatedly we are not scared of and will not be intimidated by any threats," Turkish Foreign Minister Mevlut Cavusoglu said, adding: "Economic threats against Turkey will get nowhere."
Turkish President Recep Tayyip Erdogan's spokesman Ibrahim Kalin earlier said Ankara would "continue to fight against them all", referring to IS and the YPG.
Trump on Sunday warned the US would "devastate Turkey economically if they hit Kurds".
While there have been tensions over American training of the YPG under the Kurdish-led Syrian Democratic Forces (SDF) alliance, there appeared to be some improvement on the issue after Trump said last month 2,000 American troops would withdraw from Syria.
Ankara welcomed the pullout decision after Erdogan told Trump in a phone call that Turkey could finish off the last remnants of IS.
Trump had also pushed for the creation of a 30-kilometre (20-mile) "safe zone" in his tweet but offered no details.
Cavusoglu added that Turkey was "not against" a "security zone" in Syria, during a press conference in Ankara with his Luxembourg counterpart Jean Asselborn.
- Renewed tensions -
Turkey views the YPG as a "terrorist offshoot" of the outlawed Kurdistan Workers' Party (PKK), which has been waging an insurgency against the Turkish state since 1984.
The PKK is blacklisted as a terrorist organisation by Ankara, the United States and the European Union.
Spokesman Kalin added it was "a fatal mistake to equate Syrian Kurds with the PKK".
There has been growing friction between Turkey and the US over the fate of the YPG, especially after US Secretary of State Mike Pompeo this month said Washington would ensure Turkey would not "slaughter" Kurds.
And before a visit to Ankara last week, White House National Security adviser John Bolton said the US retreat was conditional on the safety of the Kurdish fighters, provoking angry retorts from Turkish officials.
But Pompeo on Saturday said he was "optimistic" a way could be found to protect Syrian Kurds while allowing Turks to "defend their country from terrorists".
The threat of new sanctions hit the Turkish lira which weakened after 1100 GMT to reach over 5.5 to the US dollar, a loss of over one percent in value on the day.
Washington previously hit Ankara with sanctions last August over the detention of an American pastor in Turkey.
The lira plunged to seven dollars at the height of tensions.
But to Turkey's relief, the US sanctions were later lifted after Pastor Andrew Brunson was released by a Turkish court in October.
- 'Radical solution' in Idlib -
Turkey previously launched military offensives in northern Syria in 2016 and 2018 respectively against IS and the YPG. In early 2018, Syrian rebels backed by Turkish military forces captured the YPG's northwestern enclave of Afrin.
Ankara, which supports Syrian opposition fighters, is also involved in the last rebel bastion of Idlib, where Turkey has agreed a buffer zone deal with Damascus ally Russia.
But the deal has not stopped an assault by jihadists in Syria. Hayat Tahrir al-Sham (HTS), an alliance led by jihadists from Al-Qaeda's former Syrian affiliate, last week extended its administrative control over the whole of the Idlib region.
Syria's National Coalition, the leading opposition body, on Sunday called for a "radical solution" to put "an end to its (HTS) presence" in Idlib.
"If Idlib is a terrorists' nest, those responsible are not the Syrians who live in the region or Turkey but the regime and the countries which support (Damascus)," Cavusoglu said, claiming that the statements that HTS took 50 percent of Idlib are "not true".
Cavusoglu added that the Idlib deal was being "successfully applied" and that "our teams are working together to solve the minor issues".