Somalia fighting kills more than 1,000

"Unfortunately it appears, according to reports that we are receiving, there have been heavy casualties on the other side," Meles told a press conference in Addis Ababa.

"We got reports of more than 3,000 wounded in a Mogadishu hospital. Those who died are well over 1,000," the prime minister said.

"Some are Somali but a significant number of them are not Somali. We regret the death of Somalis, the others are not so much regretted," he added.

Earlier, the International Committee of the Red Cross more than 800 wounded had been reported at hospitals the agency was in contact with. Thousands have fled their homes, the agency's spokeswoman Antonella Notari said in Geneva.

"Thousands of people are fleeing their homes in the combat zone," she said.

The refugees for the moment appear to be remaining in Somalia. "We have little indications about border crossing to Kenya and Ethiopia," the spokeswoman said.

"The ICRC appeals to all the combatants to respect civilians and medical personnel and especially the wounded or captured fighters."

Heavy fighting between Islamist force and an allied Somali government-Ethiopian troops erupted last week at the expiry of a Islamist deadline for Ethiopian soldiers to pull out of the country.

The Islamist movement has retreated from the frontlines in south and central Somalia, but vowed to wage a long-term war against Addis Ababa, which it accused of invasion.