WASHINGTON — Somalia announced that obstacles to Ethiopia’s participation in the new African Union mission in Somalia (AUSSOM) have been overcome, and the final stage of the composition and size of Ethiopian forces is expected to be sorted out shortly. Somalia previously threatened to expel Ethiopian troops from the African Union peacekeeping mission unless Ethiopia renounced its controversial memorandum of understanding (MOU) with Somaliland, the breakaway region of Somalia. Under the terms of the MOU, Somaliland would lease about 20 kilometers (12 miles) of its Gulf of Aden coastline to landlocked Ethiopia’s naval forces and in exchange — according to