Turkey on Friday said it would not rest until it drains “the terrorist swamp” in northeastern Syria, a territory controlled by a Kurdish group helping the U.S.-led coalition decimate the Islamic State (ISIS/ISIL).

“We won’t stop until we drain the terrorist swamp next door. We won’t rest until justice is served,” Fahrettin Altun, the chief spokesman for Turkish President Recep Tayyip Erdogan, vowed on Friday via Twitter, the state-run Anadolu Agency (AA) reported.

Turkey has long considered the U.S.-allied People’s Protection Units (YPG) to be an extension of the Marxist-Leninist terror group known as the Kurdistan Worker’s Party (PKK) — whose members have traditionally attacked Turkish police and government targets in a struggle that has left at least 40,000 people dead.

Referring to the PKK and the YPG, Altun claimed, “Terrorists have killed more than 2,000 innocent people in Turkey since 2015. Many of those attacks were planned in northern Syria. The Turkish people suffered more than their fair share.”

To the dismay of the United States, Turkey has been planning to launch an attack to clear the American-backed YPG and its allies from their homeland in northern Syria, east of the Euphrates.

Despite Turkey’s concerns over the YPG, the United States continues to provide support to the Kurdish fighters, arguing that they are the most effective force against ISIS, which still controls a small pocket of land in northern Syria near the Iraqi border.

The U.S. support for the Syrian Kurdish fighters has strained the relationship between NATO allies Washington and Ankara.

YPG fighters make up the armed branch of the Kurdish Democratic Union Party (PYD) that has maintained control over northern Syria with the help of the United States.

In the wake of U.S. President Donald Trump’s announcement last month that his administration will withdraw the American troops from Syria, the United States has repeatedly warned Turkey against attacking the YPG and its affiliates.

YPG fighters lead and make up the majority of the U.S-backed Syrian Democratic Forces (SDF), a Kurdish-Arab alliance that continues to fight ISIS.

Kurds blasted the U.S. withdrawal from Syria as a “betrayal,” noting the move would leave them vulnerable to attacks by Turkey and could lead to a resurgence of ISIS.

The Islamic State still controls about one percent of the territory it once held in Iraq and Syria from where it is still able to carry out deadly attacks. On Wednesday, ISIS claimed responsibility for an attack that killed at least 19 people, including four Americans, and wounded others, including three U.S. service members, marking the deadliest assault on United States forces since they deployed on the ground in Syria in 2015.

Turkey claimed that “100-plus” attacks by the PKK/YPG, ISIS, and the religious movement led by U.S.-based Islamist cleric Fethullah Gulen — designated as the Fethullahist Terror Organization (FETO) by Erdogan – have killed over 2,000 “innocent Turkish people” since 2015.

Last month, Trump announced plans to pull out the 2,000 American troops from Syria and hand the fight against ISIS to Turkey, a move that some analysts believe effectively gives Ankara the green light to attack the YPG.

U.S. National Security Adviser John Bolton, however, conditioned the American troops’ withdrawal on ensuring the lasting defeat of ISIS and assurances by Turkey that the Kurds will be safe.

Turkey dismissed Bolton’s request to ensure the safety of the U.S.-allied Kurdish group as a “very serious mistake.”

Making a distinction between the predominantly Kurdish population in northern Syria and the American-backed YPG, Erdogan asserted that the looming operation is only intended to clear the Kurdish militia from the area. However, the Kurdish-majority locals in northern Syria accused Turkey of forcing a demographic change along its border with Syria last year when Ankara conquered Afrin.

Specifically, when Turkey and its Arab proxies wrested control of northern Syria’s Afrin region from the YPG, the Kurdish locals reportedly accused Ankara of ethnic cleansing as well as seizing, looting, and destroying their property.

Locals observed that Turkey was flooding the region with Turks and their Arab allies — Syrian opposition groups like the Free Syrian Army (FSA).

Bolton revealed that the Trump administration is planning to leave behind a residual force in southern Syria to combat the growing Iranian threat in the region.

Moreover, there are no plans to pull out the more than 5,000 American service members in Iraq who are expected to be authorized to carry out operations in neighboring Syria if necessary.

President Trump has agreed to slow down the Syrian withdrawal process amid concerns of an impending Turkish attack on the Kurds and ISIS’s ongoing terror campaign.

The ISIS attack on Wednesday is a testament to independent and U.S. government assessments that the jihadi group remains a menace.

In November 2018, the Pentagon’s inspector general, a watchdog agency, reported that the jihadi group has morphed into “an effective clandestine ISIS organization” that “has moved underground and is acting as an insurgency” still in both Iraq and Syria even though it only controls one percent of the territory it once held.