The United Nations has yet to reach an agreement with Damascus on the use of crucial aircraft by an expanded UN ceasefire monitoring mission in Syria, UN Security Council envoys told Reuters.
Amateur footage captures shelling in the Syrian city of Homs as a week-old ceasefire has yet to halt violence in the worst-hit parts of the country.
Reuters have reported Joint special envoy on Syria Kofi Annan has told the UN Security Council that a "bigger" Syrian observer mission is needed immediately, despite ongoing violence. Mr Annan told the Council that swift deployment of more observers could change the political dynamics.
UN observers have arrived in areas of Syria, as activists claim that rebel stronghold areas have been bombarded by heavy shelling.
The Syrian government have signed a UN agreement allowing a ceasefire monitoring mission to take place in the country. Military observers said they would stay in Syria until the "task has been completed", but would not discuss the matter further.
Syria and the United Nations have signed an agreement in Damascus on the terms of the ceasefire monitoring mission, according to Reuters. The Syrian government have agreed to the protocol on the deployment of more observers.
A Syrian activist group has said clashes between troops and army defectors in an eastern city have left at least one person dead today.
The Britain-based Syrian Observatory for Human Rights said the clashes in Deir el-Zour also wounded three civilians.
China has said that it is considering sending observers to monitor a week-old truce in Syria, that has so far failed to put an end to a year of bloodshed.
China is "seriously studying" the idea, Foreign Ministry spokesman Liu Weimin told a daily news briefing.
United Nations Secretary-General Ban Ki-moon has said he is not "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 UN observer mission.
Mr Moon said in a letter to the council that he will consider developments on the ground, including the consolidation of the ceasefire, before deciding when to deploy the expanded mission, which is larger than the 250 observers initially envisaged.
– Ban Ki-moon, UN Secretary General
Violent incidents and reports of casualties have escalated again in recent days, with reports of shelling of civilian areas and abuses by Government forces. The Government reports violent actions by armed groups. The cessation of armed violence is therefore clearly incomplete.