Somalia's president has appealed to Islamist insurgents to negotiate as intermittent fighting continued for an eighth day in the capital, Mogadishu.
Sheikh Sharif Sheikh Ahmed told the BBC the clashes were displacing thousands of the city's residents each day.
But his former ally and Islamist spiritual leader Sheikh Hassan Dahir Aweys rejected his overture.
He told the BBC talks were not possible while African Union troops were in the city where they are guarding key sites.
The United Nations refugee agency says about 30,000 people have been forced from their homes in the last week.
It is estimated more than 100 lives have been lost since a combined force of militant Islamic groups - al-Shabab and Hisbul-Islam, which are accused of links with al-Qaeda - launched their offensiveAnother prominent Islamist leader, Omar Iman Abou Bakr, told the BBC most government soldiers had fled, and those remaining were being protected by soldiers from the African Union.
The 4,300 AU peacekeepers, in the capital to bolster the government, do not have the mandate to pursue the insurgents.
President Ahmed, a moderate Islamist, was elected as president by MPs as part of a UN-backed peace initiative in January.
But even his introduction of Sharia law to the strongly Muslim country has not appeased the guerrillas.
On the BBC's Somali Service, Mr Aweys accused the government of being unelected, unrepresentative and said it should not have been imposed on the country and repeated his call for the AU to leave.
But AU envoy Nicholas Bwakira said AU peacekeepers would not pull out of the country. "It would be unacceptable that Shabab/al-Qaeda take over government in Somalia. This is a group of war criminals," he said.
"There are several members of al-Qaeda, 300 to 400 who are training the Shabab. They have also received heavy armaments from outside. They have received support logistically, financially. We are aware of that," he told the BBC's Focus on Africa programme.
But the UN envoy to Somalia, Ahmed Ould Abdallah said he wanted Somali Islamists - such as Mr Aweys - removed from both the UN and US terror lists, to help dialogue.
"No-one who is on the UN Security Council list of terrorists can be president, or prime minister, because he cannot sit in an office. Even travelling... he can be in trouble," he said in Nairobi.
"Those who are on the US list, we are ready to lobby for them."
It is estimated that more than 16,000 civilians have been killed by fighting since the start of 2007 and more than one million are internal refugees.
Friday, 15 May 2009