The UN Assistance Mission in Somalia on Monday began its task of assisting peace-building and political reconciliation in the war-torn Horn of African nation, dpa reported.
Nicholas Kay, a veteran British diplomat, arrived in Mogadishu to open the UNSOM office.
The challenges facing the country are "tremendous, but we must work hard to seize the moment," he said.
"The people of Somalia have asked the UN for a new partnership to match their aspirations," he said in a statement. "The UN effort will become more unified, more joint and more effective - based on the principles of true partnership with the African Union and all other partners of Somalia."
UNSOM's mandate is to advise the Mogadishu government and the African Union-led peacekeeping operations, which comprise more than 10,000 military and civilian personnel, on governance and security reform.