Meanwhile, the United States has sent additional diplomats to Syria since May to help address the country's conflict, US Secretary of State Rex Tillerson stressed in a speech.
"Since May, the United States has deployed additional diplomats to the affected areas in Syria working with the United Nations, our partners in the global coalition to defeat ISIS [Daesh] and various non-governmental organizations," Tillerson said.
"The United States will maintain a military presence in Syria focused on ensuring ISIS [Daesh] cannot re-emerge," Tillerson stressed in a speech on the US strategy in Syria.
US senior diplomat also explained that Washington and its allies are working to develop a plan to take out al Qaeda terrorists attempting to set up a base of operations in the Syrian city of Idlib.
Meanwhile, Rex Tillerson also explained that the US needs Russia’s cooperation in order to strengthen the de-escalation area in southwestern Syria.
"Since July the United States has worked with Russia and Jordan to establish the de-escalation area in the southwest part of Syria. It has achieved a ceasefire, ended indiscriminate bombing of civilian populations, and with only a few exceptions it has thus far held up well," Tillerson said. "We need Russia to continue to work with the United States and Jordan to enforce this de-escalation area."
However, Moscow must increase pressure on Damascus in order to advance the Geneva peace process, US Secretary of State pointed out.
"The Assad regime clearly looks to Russia as a guarantor of its security. Russia therefore has a meaningful role to play in persuading the Assad regime to engage constructively in the Geneva process," Tillerson said. "Russia must put new levels of pressure on the regime to not just show up in Geneva but credibly engage with the UN efforts and implement to bring the outcomes."
"The United States hears and takes seriously the concerns of our NATO ally Turkey," Tillerson said. "We recognize the humanitarian contributions and military sacrifices Turkey has made toward defeating ISIS [Daesh], toward their support of millions of Syrian refugees and stabilizing the areas of Syria it has helped liberate."
Tillerson also said the United States "must have Turkey’s close cooperation" in order to achieve "a new future for Syria that ensures security for Syria’s neighbors."
Syria has been engulfed in a civil war since 2011, with government forces fighting numerous opposition factions and terrorist groups.
The international community has taken a number of steps aimed at settling the crisis, including through negotiations in Geneva and Astana. The last round of UN-mediated Geneva talks took place in December.
The US military involvement in Syria has not been approved by the UN Security Council or the Syrian government.