Key Points

• President Joe Biden called the overthrow of Syria’s dictatorship a “historic opportunity” for the Syrian people.

• He also warned of some risks posed by uncertainty, such as a resurgence of ISIS.

• The United States plans to support Syria and its neighbors during their political transition.

President Joe Biden applauded the overthrow of Syria’s dictatorship in remarks Sunday but warned of uncertainty during the country’s political transition.

“This is a moment of historic opportunity for the long-suffering people of Syria to build a better future for their proud country,” he said from the Roosevelt Room of the White House. “It is also a time of risk and uncertainty. As we address the question of what comes next, the United States will work with our partners and stakeholders in Syria to help them seize the opportunity to manage risk.”

The United States will support Syria’s neighbors, including Jordan, Iraq, Lebanon and Israel, during the transition period and send senior officials to the region, Biden said. He also vowed to continue the mission against ISIS and ensure the security of detention centers in Syria housing ISIS fighters.

“We are clear about the fact that ISIS will try to take advantage of the new vacuum to restore its capacity and create a safe haven. “We will not let that happen,” Biden said.

He added that US forces carried out a dozen precision airstrikes in Syria on Sunday, targeting ISIS camps and operatives.

But he noted that it is not just ISIS that poses a threat. Biden said the United States will remain vigilant, adding that some of the rebel groups that toppled the Assad regime have their own records of terrorism and human rights abuses.

“They are saying the right things now, but as they take on more responsibility, we will evaluate not only their words but also their actions,” he said.

The United States will also help “all Syrian groups” establish a sovereign, independent government. That commitment will include humanitarian aid to help Syria after 13 years of civil war.

Biden also said his administration is committed to returning Austin Tice to his family. Tice, an American journalist, was kidnapped in Damascus in 2012 and detained by the Syrian government. Biden said the United States believes Tice is alive.

Syrian rebel forces took the capital Damascus on Sunday. Russia’s Foreign Ministry said President Bashar al-Assad has resigned and left the country, ending his family’s decades-long dictatorship in Syria.

“We’re not sure where he is, but he’s said to be in Moscow,” Biden said, later adding that Assad should be held accountable.

Assad assumed leadership of the country in 2000, after the death of his father. Assad’s allies included Russia, Iran and the Lebanese militant group Hezbollah. Biden said the three allies are “much weaker” now than when he took office.