"The US is a large government, but they are supporting Ethiopia, supporting the dictator [Ethiopian prime minister] Meles Zenawi, who is killing our people," Ahmed said.
"Instead, we appeal to European countries, to the US, to the UN, to support us."
The warning came as a series of attacks killed one civilian and wounded four others in Mogadishu, the Somali capital, on Saturday.
Overnight grenades were fired at the Hotel Lafweyn where Somali National Reconciliation Congress delegates are staying, injuring two, Abduwahid Mohamed, police spokesman, said.
"They suffered small injuries, but police are investigating the incident," he said.
Last week, Maalim Harun Maalim Yusuf, a respected Somali elder participating in the government-sponsored reconciliation effort, was assassinated.
The peace process is supported by the UN and Western nations but they have been boycotted by the Islamic courts and a large part of the capital's dominant Hawiye clan.
The Islamist courts is planning parallel talks in Asmara on September 1, an event that analysts warned would further polarise efforts to restore security in the nation of 10 million people.