Nasr al-Hariri Head of the HNC opposition group holds documents during a news conference in Geneva, Switzerland March 24, 2017.

Syrian opposition leader Nasr al-Hariri said during an interview with Al Arabiya’s sister channel Al Hadath that a political solution could never be reached in Syria without America’s participation.

Al-Hariri accused the regime and its allies of pursuing a systematic policy of taking control of areas west of the capital Damascus, warning of what he described as a project planned by Iran more than a century ago.

Hariri said Iran was committing war crimes in western Damascus for sectarian reasons.

The White House said that the removal of Assad is no longer a priority for the Trump administration. White House spokesperson Sean Spicer said US must accept “political reality” at his briefing on Friday.

“There is a political reality that we have to accept in terms of where we are right now,” Spicer said.

“We lost a lot of opportunity the last administration, with respect to Assad.”

He added that the US must focus “on defeating ISIS.”