(CNN) -- The British Foreign Office is warning British nationals to avoid travel to any part of Somalia because it believes "terrorists are in the final stages of planning attacks in Mogadishu."
"Any British citizens in Somalia should leave," the office's website says, citing "a specific threat to Westerners."
"Terrorist groups have made threats against Westerners and those working for Western organizations," it said.
The U.S. State Department warned Americans in December to avoid Somalia; that advice still stands.
Neither the United States nor the United Kingdom has diplomatic representatives in Somalia who could help citizens who get into trouble.