"The United States will maintain a conditions-based and ISIS-focused military presence in Syria. As part of that presence, we will continue to train local security forces in Syria," Tillerson said.
In northern Syria, Turkey is fighting to dismantle the armed Kurdish presence along the border, heightening tensions between Ankara and Washington, which has supported the groups now being attacked by its fellow member of the North Atlantic Treaty Organization (NATO).
"We are keenly aware of the legitimate security concerns of Turkey, our coalition partner and NATO ally," Tillerson said. "We will continue to be completely transparent with Turkey about our efforts in Syria to defeat ISIS [Daesh], and we stand by our NATO ally in its counterterrorism efforts."
Tillerson announcement comes after Turkish President Recep Tayyip Erdogan called on the US earlier in the day to "stop this theater with Daesh in Syria," adding that a decision by the US to continue to fund the Syrian Kurdish YPG militia would affect Turkey's decisions.
The situation in the region escalated earlier this year, after US Col. Thomas Veale said that the US-led coalition had been training the Kurdish Syrian Democratic Forces (SDF) to create a 30,000-strong force to maintain security along Syria's borders.
Following the revelation, Turkey launched an operation dubbed "Olive Branch" in Syria's Kurds-dominated Afrin. The operation is carried out against Kurdish SDF-affiliated People's Protection Units (YPG), which Ankara believes have links to the Kurdistan Workers’ Party (PKK), designated as a terrorist organization in Turkey.
On Daesh Influence in Afghanistan and West Africa
Speaking further, the US top foreign affairs diplomat said that the US-led coalition must redouble its efforts as the terror group attempts to evolve into an insurgency that threatens Afghanistan, West Africa, the Philippines and other countries.
"As ISIS [Daesh] continues to evolve, so must the coalition. ISIS is attempting to morph into an insurgency in places like Afghanistan, the Philippines, Libya, West Africa, and others, and is trying to carve our and secure safe havens," Tillerson said.
Tillerson continued by saying that the United States wanted quick implementation and enforcement of UN Security Council Resolution 2396 to help fight threats posed by foreign terrorist fighters in the next phase of the battle against Daesh.
The resolution, adopted unanimously by the Security Council in 2017, calls on UN member states to step up coordinated efforts to prevent the travel, recruitment and financing of foreign terrorist fighters.
Tillerson delivered his speech at the Global Coalition to Defeat ISIS Ministerial that was held in Kuwait city earlier on Tuesday.
Upon finishing the meeting, the minister adopted a joined statement, in which the top officials assured that the coalition would continue fighting Daesh in Iraq and Syria until it achieves an enduring defeat of the terrorist group.
"Enduring defeat will come when ISIS/Daesh no longer has safe havens from which to operate; when it no longer poses a threat to our homelands; and when it can no longer convey its ideology of hate globally," the statement said.
The coalition said it must remain focused on the situation in both Iraq and Syria to secure gains, but also adapt in order to deal with the terror group's "global ambitions."
The statement said the coalition would use a whole-of-government approach to interrupt Daesh networks, branches and affiliates, as well as deny fighters the freedom of movement around the world.
The coalition also underlined the need to combat the ideology put forward by Daesh by doubling efforts to deny the group the opportunity to exploit social media and the internet.