(Adds quote, details) ADDIS ABABA, Dec 27 (Reuters) - Ethiopian troops waging war against rival Islamists in Somalia should leave the country immediately, the African Union (AU) chief said on Wednesday. "We call for the withdrawal of Ethiopian troops without delay," AU chairman Alpha Omar Konare said in a statement. "We appeal for urgent support for the transitional government and the withdrawal of all troops and foreign elements from Somalia." Konare urged Somalia's interim government and the Somalia Islamic Courts Union to end all hostilities and resume Arab League-sponsored peace talks that collapsed in Sudan last month. He said an AU-led mission planned to visit both sides in Somalia in the coming days. After a week of artillery and mortar duels between the two sides that spiralled into open war, Ethiopian-backed government troops were advancing on the Islamists' stronghold Mogadishu. Somalia's envoy to Ethiopia said the joint force planned to besiege the capital until the Islamists laid down their arms.
