US ambassador warns Syria regime over violence
The US permanent representative to the UN has warned Syria not to intensify violence ahead of a ceasefire proposed by the UN and Arab League.
Susan Rice said the Security Council had to respond urgently if the Syrian government failed to keep its pledge to end military operations by 10 April.
Syria says it will honour the deadline, but Ms Rice said she doubted this.
Activists say the government is stalling for time so it can crush the uprising before UN monitors arrive.
They say attacks on opposition strongholds are continuing.
An advance team from the UN Department of Peacekeeping Operations (DPKO) is due in Damascus imminently to discuss the deployment of the monitors.
The UN and Arab League envoy to Syria, Kofi Annan, will hold talks in Geneva on Wednesday with Norway's Maj-Gen Robert Mood, who will lead the advance team.
Gen Mood is a former head of the UN Truce Supervision Organisation (UNTSO), the UN peacekeeping operation in the Middle East.'Urgent and serious'
Ms Rice said that "from the US point of view, and I think the point of view of many member states, what we have seen since 1 April is not encouraging".
She said the US was "concerned and quite sceptical that the government of Syria will suddenly adhere to its commitments".
If the Syrian authorities use the time up to 10 April to intensify rather than decrease the violence, the Security Council would "need to respond to that failure in a very urgent and serious way", she said.
Officials say Damascus has committed to begin withdrawing its forces from in and around population centres on Sunday and to finish by 10 April, with a general ceasefire within 48 hours contingent on that withdrawal.
Western powers are circulating a draft Security Council statement supporting the ceasefire initiative, on which the 15 member states were briefed by Mr Annan on Monday. The statement will be discussed over the next two days.
Ms Rice acknowledged that the Security Council was divided over whether to take action to pressure Syrian President Bashar al-Assad.
But she suggested that if the Syrian government continued its military offensive despite its commitment to the plan, the diplomatic calculations of Syria's allies might change, reports the BBC's Barbara Plett at the UN.
The ceasefire is only one part of Mr Annan's peace plan, which also calls for a political process to address the "aspirations" of the Syrian people, the release of detainees, the delivery of humanitarian aid, free movement for journalists, and the right to protest.
Meanwhile, the president of the UN General Assembly, Nasser Abdul Aziz al-Nasser, said he had asked Mr Annan to brief the world body on his Syria peace mission.
No date has been set, but Mr Nasser said he had suggested 13 April, our correspondent reports.Turkey criticism
In Damascus, the head of the International Committee of the Red Cross (ICRC), Jakob Kellenberger, has been meeting top Syrian officials to try to persuade them to allow aid workers better access to those who have been wounded or displaced by the conflict.
Mr Kellenberger is also pressing the Syrian authorities to implement a daily two-hour ceasefire, as stipulated in the peace plan proposed by Mr Annan.
Russia's foreign ministry says Syria's government has informed Moscow it has started implementing Mr Annan's plan to end the unrest.
Earlier, Turkish Prime Minister Recep Tayyip Erdogan accused the Security Council of indirectly supporting the oppression of the Syrian people by failing to adopt a united stance on the crisis.
Mr Erdogan said the Security Council was standing by with its "hands and arms tied" while Syrian people were dying every day.
By not taking a decision on Syria, it had "indirectly supported the oppression, he said. To stand by with your hands and arms tied while the Syrian people are dying every day is to support the oppression", he added.
He told members of parliament from his governing AK Party that Turkey would not turn its back on the Syrian people.
China and Russia have twice vetoed Security Council resolutions condemning President Assad's government for turning the army on civilians.