"At the same time, we are waiting for Mr. Annan to take tangible steps towards the armed terrorist groups and take commitments from the states which support and sponsor them to halt violence in Syria," the state-run Syrian Arab News Agency quoted Minister of Information Adnan Mahmoud as saying.
The comments come after Derek Chollet, the senior director for strategy at the National Security Council, said the plan was "failing" during a Senate hearing last week.
The White House admission creates extra pressure on the administration to take extra measures to quell the bloodshed in Syria, where at least 10,000 people have been killed since the uprising against President Bashar al-Assad began a year ago. Senate Foreign Relations Committee Chairman John Kerry (D-Mass.) is in the region this week meeting with area leaders about possible next steps, including arming the rebels and creating safety zones protected by the international community.