File Photo: The U.S. flag flutters on a military vehicle in Manbej countryside, Syria May 12, 2018. (Xinhua/REUTERS)

WASHINGTON, Feb. 5 (Xinhua) -- A U.S. senior military official on Tuesday warned of the danger posed by the Islamic State (IS) forces to Syria and said U.S. talks with Afghan Taliban were in "very, very early" stages.

General Joseph Votel, the chief commander of U.S. Central Command, told the Senate Armed Services Committee in a hearing that despite the progress of the multinational campaign against the IS in Syria, "it is important to understand that ... the fight against IS and violent extremists is not over and our mission has not changed."

The commander that oversees U.S. troops in the Middle East and Afghanistan added that the current military gains achieved by a U.S.-led coalition "can only be secured by maintaining a vigilant offensive against the now largely dispersed and disaggregated ISIS that retains leaders, fighters, facilitators, resources and the profane ideology that fuels their efforts," and some remaining IS fighters have "dispersed" and "gone to ground."

The IS forces have the ability of "coming back together," he noted.

When asked whether he was asked for his advice about a Syria withdrawal before Trump announced his decision last year, Votel said that "I was not consulted."

"I was not aware of the specific announcement. Certainly we were aware that he had expressed a desire and intent in the past to depart Syria," he noted.

The U.S.-led multinational coalition has been engaged in an operation to drive out the IS militants from their last stronghold in the eastern Euphrates region in eastern Syria.

In December, Trump abruptly announced his decision to withdraw U.S. troops from Syria, citing that the local IS force has been largely defeated.

Speaking of the U.S. talks with Afghan Taliban, Votel said they were in "very, very early" stages and that the Afghan government would have to be part of the solution.

"I would characterize where we are in the process as very, very early in the process," he said. "We clearly recognize that they (Afghan government) have to be a part of this solution and must be in the negotiation aspects of this, we can't do that on their behalf."

The remarks were also apparently different from what U.S. Special Representative for Afghan Reconciliation Zalmay Khalilzad said last month that the United States and Afghan Taliban had made significant progress on vital issues after six days' consultations in Qatar.

The meetings were "more productive than they have been in the past. We made significant progress on vital issues," Khalilzad tweeted.

Trump later expressed optimism about the negotiations, tweeting that they "are proceeding well in Afghanistan after 18 years of fighting."

There are about 14,000 U.S. troops currently deployed in Afghanistan, and the Trump administration reportedly planned to bring half of them home, sparking fear and criticism even among the Republicans.