Gen. Robert Mood and U.N. peacekeeping chief Herve Ladsous will meet the 15 council ambassadors behind closed doors to give their assessment of the upsurge in violence by government forces and the opposition in recent days, which led to Mood's suspension of patrols and all other activities by the 300 unarmed observers on Saturday.
Annan's six-point plan calls for an immediate cessation of fighting, first by the Syrian government and then the opposition, with the goal of launching a political dialogue.
British Ambassador Mark Lyall Grant said Monday that council members are eager to hear what Mood thinks.
"I think there will be a lot of member states of the council, including us, who will be questioning now what the future is for the mission and, therefore, by extension the Annan plan, in light of these recent developments on the ground" he said.
The three-month mandate of the observer mission expires July 20. Lyall Grant said he could not rule out that the council might end it before then.
"I think we are going to have to review it in the light of what has happened," he said.
Lyall Grant blamed the Syrian regime for the mission's decision to suspend its patrols in light of the violence.
"Their brutality against their own civilian population has led to the sort of spikes in violence that we've now seen," he said.
Russia and China, who have close ties to Syria, have vetoed two resolutions that mentioned the threat of sanctions against President Bashar Assad's regime. But they did vote for the resolution authorizing the observer mission and endorsing Annan's six-point plan.
"We're very concerned about the suspension of mission observers in Syria and we believe that the parties - all parties in Syria - should offer full cooperation to mission observers," China's U.N. Ambassador Li Baodong, the current Security Council president, told reporters late Monday.
"It's very important for them to implement Kofi Annan's six-point peace plan and also (the) U.N. resolution," he said. Li said there have been "some different conflicting reports" about the current situation in Syria.