The violent struggle between the Syrian government and opposition forces risks tearing the country apart and spilling over its borders to spread sectarian war across the region, former UN Secretary General Kofi Annan warned on Friday.
Annan called on the international community to "get its act together" and said that his successor as peace envoy to the country, Lakhdar Brahimi, will need the support of all members of the UN Security Council - including Russia - to have a chance of a peaceful resolution to the Syrian crisis.
Annan quit as the UN and Arab League's envoy to Syria in August, complaining of a lack of support from the Security Council, where Russia and China have blocked resolutions designed to put pressure on president Bashar Assad.
The Ghanaian told the BBC Radio 4 Today programme: "If the international community doesn't get its act together and find a way of pressuring the parties to give up their ambitions on the battlefield, we are going to see a situation where sectarian war will spread in Syria and probably go beyond its borders."
The Syrian crisis has taken the lives of thousands
"Syria is not Libya," he continued. "Libya imploded, Syria will not implode but in all likelihood explode, and explode beyond its borders.
"That mosaic of Syria, if we tear it apart, is going to be very difficult to put together again."
Annan said that the veteran Algerian diplomat Mr Brahimi, who took up his post as peace envoy at the start of this month, will be dependent on strong support from the Security Council to make an impact.
"Lakhdar Brahimi is experienced, he can make a contribution if he gets the support he needs - not passive support, but real support from the Security Council," he said.
Asked if this must include Russia, Annan replied: "Exactly. Alone, he cannot do it."