Secretary-General Ban Ki-moon is calling the situation in Syria "highly precarious" but says he's still recommending a 300-strong U.N. observer force to try to help bring peace.
Despite the Syrian government's agreement to cease all violence, Ban said attacks have escalated including "shelling of civilian areas, grave abuses by government forces and attacks by armed groups."
Ban urged the Security Council to quickly approve the expanded force, and stressed its size is subject "to continuing assessment."
Ban said he emphasized the Syrian government's responsibility to ensure freedom of movement and use of helicopters by the observers in a meeting Thursday morning with Syria's U.N. Ambassador Bashar Ja'afari, who assured him of the government's full support.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
UNITED NATIONS (AP) _ Secretary-General Ban Ki-moon said late Wednesday he isn't underestimating the gravity of the situation in Syria but believes there is an opportunity for progress and recommended the Security Council approve a 300-strong U.N. observer mission.
Ban said in a letter to the council obtained by The Associated Press that he will consider developments on the ground, including consolidation of the cease-fire, before deciding on when to deploy the expanded mission, which is larger than the 250 observers initially envisioned.
Syria accepted a six-point plan by Kofi Annan, the joint U.N.-Arab League envoy, to end more than a year of bloodshed and launch political talks to end the conflict. But Ban said President Bashar Assad's government has only partially implemented its commitments.
The U.N. chief said the level of violence dropped markedly on April 12, the day the cease-fire called for by international envoy Kofi Annan went into effect, but that violent incidents and reported casualties have escalated again in recent days and "the cessation of armed violence in all its forms is therefore clearly incomplete."
At the same time, Ban said, the Syrian government and opposition have continued to express their commitment to a cease-fire and have agreed to cooperate with a U.N. observer mission.
"I remain deeply concerned about the gravity of the situation in the country," he said. "However, without underestimating the serious challenges ahead, an opportunity for progress may now exist, on which we need to build."
The Security Council authorized an advance team of 30 observers for Syria last Saturday and a small group are already at work.
The secretary-general called on the council to approve an expanded United Nations Supervision Mission in Syria, to be known as UNSMIS, comprising an initial deployment of up to 300 military observers in approximately 10 locations throughout the country, for an initial period of three months.
It would be backed up by support personnel included advisors with political, human rights, civil affairs, public information, public security, gender and other expertise, he said. Ban said this week the mission needs helicopters, and in his letter he reiterated that "appropriate air transport assets" are required "to ensure mobility and capacity to react quickly to reported incidents."
The Security Council was scheduled to discuss Ban's letter and recommendations at a closed meeting Thursday morning.
Ban said Syria has not fully implemented its initial requirement under Annan's six-point plan to withdraw troops and heavy weapons from towns and cities and return them to barracks. He said these requirements are "critical" to sustain a cease-fire.
Ban said members of the small advance team on the ground in Syria enjoyed freedom of movement on a visit to the southern city of Daraa on Tuesday where they saw buses and trucks with soldiers dispersed throughout the city.
On Wednesday, he said, the advance team visited Jobar, Zamalka and Arbeen in suburban Damascus and reported the presence of military at checkpoints and around some public squares and buildings in all three locations. In Arbeen, he said, one armored personnel carrier was hidden, covered by a plastic sheet.
"The situation in Arbeen became tense when a crowd that was part of an opposition demonstration forced United Nations vehicles to a checkpoint," Ban said. "Subsequently, the crowd was dispersed by firing projectiles. Those responsible for the firing could not be ascertained by the United Nations military observers."
The secretary-general said no injuries were observed by the advance team but one U.N. vehicle "was damaged slightly during the incident."
Ban said the team's initial request to visit Homs _ the city at the center of the 13-month conflict _ "was not granted, with officials claiming security concerns."
The U.N. chief said action on other parts of Annan's six-point plan "remains partial, and, while difficult to assess, it does not amount yet to the clear signal expected from Syrian authorities."
Regarding the right to protest freely, he said, reports from local opposition groups suggest there was "a more restrained response" to demonstrations on April 13 _ the day after the cease-fire took effect _ "but there were nevertheless attempts to intimidate protesters, including reports of incidents of rifle fire by government troops."
On detainees, Ban said "the status and circumstances of thousands of detainees across the country remains unclear and there continue to be concerning reports of significant abuses." He added that "there has been no significant release of detainees."
While the Syrian government said entry visas were granted to 53 Arab and foreign journalists, Ban said the U.N. has no further information and he again demanded that all journalists "have full freedom of movement throughout the country."
Annan's plan calls for unrestricted humanitarian access but Ban said "no substantive progress has been achieved over the last weeks of negotiations" on access to the one million people in need of aid.
"Developments since April 12 underline the importance of sending a clear message to the authorities that a cessation of armed violence must be respected in full, and that action is needed on all aspects of the six-point plan," Ban said.