The Somali government had said it hoped for a peace deal after members of the 15-nation Council met separately with its officials and opposition critics on Monday in Djibouti.

But leaders of the Islamist al Shabaab insurgent group and more hardline elements of the Eritrea-based Alliance for the Re-Liberation of Somalia (ARS) were absent. The opposition figures who did attend demanded Ethiopian forces leave Somalia.

In a statement released as Security Council members left for Sudan and the next leg of an African tour, nine Somali groups representing rights activists, women and elders lamented the "graveyards of missed and lost opportunities" in Somali history.

"The Security Council should impose targeted sanctions against any Somali leaders who are fomenting further violence and reject the Somali peace process," it said.

The group said Council members should also ask for the withdrawal of Ethiopian soldiers who helped the government oust an Islamist movement from the capital Mogadishu in late 2006.

Since then, the Shabaab -- remnants of that sharia courts movement -- have waged an insurgency of ambushes, roadside bombs and mortar attacks, sometimes briefly seizing smaller towns.

In March, Washington formally designated the militia as a foreign terrorist organisation, describing it as al Qaeda's main link in the Horn of Africa nation. Somalia has been without any effective central government since 1991.

Frequent clashes between the well-armed rebels and allied Somali-Ethiopian forces have killed thousands of civilians since early last year and uprooted at least one million.

In the latest bloodshed, insurgents hurled grenades into a video hall late on Monday, killing three people and wounding four others in Galkayo, a town north of Mogadishu, police said.

In Djibouti on Monday, Security Council members met Somali President Abdullahi Yusuf and ARS head Sheikh Sharif Ahmed. But ARS leaders who stayed behind in Eritrea denounced the talks, saying Sharif had not spoken on their behalf.

Sheikh Hassan Dahir Aweys, another top ARS official, told Reuters by telephone that Sharif had broken alliance rules by attending, and that the ARS had no plans for negotiations.

"We have isolated the government ... It is not in our agenda to talk or share any responsibilities with this government," said Aweys, who is accused by the United Nations and United States of having links to al Qaeda.