The UN condemned yesterday the killing of civilians in Sri Lanka at the weekend as a "bloodbath" in which more than 100 children died, as the government and rebels traded blame for the attacks.

Artillery strikes in the small stretch of coastline still held by the Tamil Tiger guerrillas caused major casualties among the tens of thousands of non-combatants, both sides reported.

"The large scale killing of civilians, including the death of over 100 children, over the weekend shows that the bloodbath scenario has become a reality," Gordon Weiss, the UN spokesman in Colombo, told AFP.

The rebels said the civilians had died as the military pressed ahead with its offensive, but the defence ministry accused the Tigers of firing mortars to create a humanitarian crisis and attract foreign intervention.

"They are bombarding their own civilians with heavy weapons to lay the blame on the Sri Lankan forces," the ministry said in a statement.

"Hopefully, in their calculation, this will attract the foreign countries to throw a life line to save their souls."

The government yesterday said 250 civilians had been killed or wounded in the attacks blamed on the rebels, while the pro-rebel Tamilnet website said that the weekend death toll had risen to 3,200.

Casualty claims from the war zone are impossible to verify as journalists and international monitors are not allowed to travel freely in the area.

Sri Lanka's government believes its soldiers are on the verge of defeating the Liberation Tigers of Tamil Eelam after 37 years of conflict.

At the height of their power in 2006, the Tigers - who want an independent Tamil homeland in the Sinhalese-majority island - controlled roughly a third of the island.

The Tigers have since been driven back into a sliver of land on the northeastern coast, where the UN has accused them of holding up to 50,000 Tamil civilians hostage.

Sri Lankan leaders have refused all international calls for a ceasefire, despite reports from the UN last month saying up to 6,500 civilians may have been killed and 14,000 wounded in fighting since January.