Syrian President Bashar al-Assad must step down quickly to stop the country spiralling into civil war, but should be allowed to stay in the country as he is not responsible for the unrest, the incumbent leader's uncle Rifaat al-Assad said on Thursday.

In an interview with French television, Rifaat al-Assad said months of civil unrest had effectively deprived Syria of leadership, and it now risked being torn apart by armed militias and could face a worse upheaval than neighbouring Lebanon's civil war in the 1970s and 80s.

Out of a sense of patriotism, Bashar al-Assad should speed up his departure, he said, but his presence in Syria was not untenable as blood had been shed on both sides, among supporters and opponents of the government.

He has to go, but without leaving the country. He isn't responsible, it's a historical accumulation of many things, and I'd like him to convince himself to step down, Rifaat al-Assad told LCI television.

Rifaat al-Assad is a former military commander, widely held responsible for crushing an Islamist uprising in 1982 against then president Hafez al-Assad, Bashar's father, in which many thousands were killed.

Rifaat turned against the government in the 1980s and now lives in exile. Earlier this year, his son and Bashar's cousin Ribal, who lives in exile in London, urged the Syrian leader to attempt a rapprochement with opponents to avoid civil war and an outbreak of regional conflict.

On Thursday, Ribal told BBC radio the government just wanted to cling to power. They don't want any dialogue, they are ready to do whatever, he said.

He called for the opposition to be united, to include all the country's different ethnic groups, sects and religions, as part of a process towards a peaceful transition. This could allow his cousin to get out, if somebody could give him refuge, he said.

I have been talking to people in the military and in the military secret service lately in Syria who also are tired and are against what is happening, he said. They are tired of the violence that's being used against people.

Western countries are piling pressure on Bashar al-Assad to halt the violent crackdown on protesters against his government, which has cost more than 3,500 lives by a U.N. count, since demonstrations began in March.

The Arab League has suspended Syria and given it until the end of the week to comply with an Arab peace plan to end the bloodshed.

(Reporting By Vicky Buffery. Additional reporting Avril Ormsby in London.; Editing by Geert De Clercq and Sophie Hares)