"While the nature of US support to partner forces will adjust as the coalition shifts from from major urban combat operations to stabilization tasks, US support will not end until the enduring defeat of ISIS and will be determined by conditions on the ground," Pentagon spokesman Eric Pahon said in a written statement Tuesday outlining the US strategy in Syria going forward.
The US military said it would also continue to support its local allies, the Syrian Democratic Forces, as they move to stabilize eastern Syria following a series of military victories over ISIS.
Military officials have long said that despite several high-profile ISIS defeats, military operations against the terror group would continue for some time.
The US-led anti-ISIS military coalition announced Monday that coalition warplanes had conducted 28 airstrikes against ISIS targets near Abu Kamal, Syria, since Friday, striking ISIS tactical units, vehicles and heavy weapons.
Despite recent reports suggesting that US support for the SDF would be curtailed, Pahon said the United States would work with the SDF and other local forces on the ground to transition to a "sustainable, self-sufficient, ethnically diverse local security forces," while also promoting "inclusive governance" that is representative of local communities liberated from ISIS rule.
Secretary of Defense James Mattis told reporters Friday that the US military mission in Syria was being reconfigured to better support diplomatic objectives, including the UN-led Geneva process aimed at bringing an end to the Syrian Civil War.
"We're changing the composition of our forces to something that supports the diplomats and the Geneva process," Mattis told reporters while en route to meetings in Egypt.
Mattis also said that the US was adjusting its support to the Syrian Democratic Forces, a mix of Kurdish and Arab troops that have led the US-backed fight against ISIS in Syria, suggesting that offensive weapons would no longer be provided to the Kurdish elements of the SDF, a change long sought by America's NATO ally Turkey.
"As the coalition stops offensive (operations), then, obviously, you don't need that, you need security -- you need police forces. That's local forces. That's people who make certain that ISIS doesn't come back," Mattis said, highlighting the US desire to shift its focus to local forces providing stability.
However, the Russian Ministry of Defense said Monday that it had begun working with Arab and Kurdish groups operating east of the Euphrates River, an area of operations for the US advisers and the US-backed Syrian Democratic Forces, highlighting an increasingly complex battle space.
In his statement Tuesday, Pahon criticized Russia and the regime of Syrian President Bashar al-Assad as impediments to stabilizing the situation there, saying that countering ISIS, al Qaeda and other terrorist groups is not of the "foremost priority" of Russia and Syria.
Furthermore, Russia and Syria do not "appear to be serious about the withdrawal of Iranian-backed militias" operating in Syria, Pahon said.