Washington announced on Friday it would leave about 400 US troops in Syria, split between two different areas, a senior administration official said.
The first 200 troops will join about 800 to 1,500 troops from European allies to set up and observe a safe zone being negotiated for northeastern Syria.
The other 200 US troops will remain at the US military outpost of Tanf, near the border with Iraq and Jordan, Reuters quoted the official as saying.
Officials said the numbers agreed on this week were not firm and could still change.
“We don’t want to see a resurgence of ISIS,” the official said.
A day earlier, the White House revealed a plan to keep “a small peacekeeping group” in Syria, an announcement which slightly changes a previous decision by President Donald Trump, who had ordered in December the withdrawal of all 2,000 US troops from the war-torn country.
He made this decision after being told European allies insisted on some US forces remaining on the ground as part of the observer force.
“We evaluate the White House decision ... positively,” Abdulkarim Omar, co-chair of foreign relations in the region held by the US-backed Syrian Democratic Forces told Reuters on Friday.
He said the decision might “encourage other European states, particularly our partners in the international coalition against terrorism, to keep forces in the region.”
The decision came after Trump spoke by phone to Turkish President Tayyip Erdogan.
The US president proposed to Erdogan that Turkish military officials and Washington "continue coordinating on the creation of a potential safe zone.”
Commenting on reports saying that the US may leave a peacekeeping force of 200 troops in Syria, Russian Presidential Spokesman Dmitry Peskov told reporters on Friday that Moscow is closely following and analyzing the evolution of Washington’s stance on the potential withdrawal.
He expressed belief that the situation is unclear for the time being.
“Washington first said something different, but later new statements could be heard,” Peskov said, adding that sometimes “we hear different statements from different agencies, so we are watching with great interest and attention the evolution of the US stance on the issue and analyzing all these statements.”
Also, Russia’s Foreign Ministry questioned the statements of US officials concerning the pullout.
"One should not believe in these statements, no matter who they come from, because on the next day they may be refuted by other political forces," Russian Foreign Ministry spokeswoman Maria Zakharova said.