Syria's main opposition group says it has serious reservations about a U.N. envoy's plan setting the stage for new peace talks to end the civil war.

The Turkey-based Syrian National Coalition says Staffan de Mistura's plan lacks the mechanism for a political transition without the presence of Syrian President Bashar Assad and allows him time to maneuver politically and consolidate gains on the ground.

In a statement after meetings with de Mistura Saturday, the group said his answers "fell short of dispelling our concerns."

The U.N. Security Council last week endorsed de Mistura's plan for new peace talks to end the conflict. It includes talks on a political transition leading to democratic elections and how best to fight terrorism. However, the future of Assad remains a sticking point.