Obama, in an executive order, declared that a national emergency with respect to Somalia was extended for another year.
"Because the situation with respect to Somalia continues to pose an unusual and extraordinary threat to the national security and foreign policy of the United States, the national emergency declared on April 12, 2010, and the measures adopted on that date to deal with that emergency, must continue in effect beyond April 12, 2012," he said in a statement.
Al-Shabaab, a militant group tied to al-Qaida, controls parts of Somalia though it has lost ground amid an offensive supported by troops from the African Union.
In January, Augustine Mahiga, U.N. special envoy to Somalia, formally moved from offices in Kenya to the Somali capital after a 17-year absence. World leaders during a one-day conference in London in February expressed optimism that Somalia was turning the corner after years of civil war.
Obama's announcement came one day after at least 12 people were killed when an improvised explosive detonated in the Somalia market town of Baidoa and a week after Somali officials were killed in an attack on a theater in Mogadishu.
There hasn't been a formal central government in Somalia since the 1990s.