The United States had previously declined to confirm Ethiopian intervention in neighboring Somalia.
But in the wake of air strikes against Somali targets since Monday acknowledged by Ethiopia, the State Department is defending the action as a response to aggression, and says Addis Ababa has acted at the request of Somalia's legitimate administration, based in Baidoa.
In a talk with reporters, acting State Department spokesman Gonzalo Gallegos urged restraint by Ethiopia and a resumption of peace talks between the transitional administration and the Islamic Courts movement.
He said, "Ethiopia has genuine security concerns with regard to developments in Somalia and has provided support at the request of the legitimate governing authority, the Transitional Federal institutions."
"We, the U.S., have urged, and continue to urge the Ethiopian government to exercise maximum restraint in intervening or responding to developments in Somalia and to assure the protection of civilians. However no Somali party should use external actors as an excuse to avoid further dialogue, " he continued.
The spokesman said Ethiopia started its military operations in Somalia in response to aggression by the Islamic militiamen, who have been on the offensive against the Baidoa administration despite a U.N. Security Council resolution adopted three weeks ago.
That measure called on the Islamists to cease further military expansion, while authorizing an East African protection and training force to shore up the embattled Baidoa authority.
Gallegos said the United States is concerned by the deteriorating security conditions and the humanitarian impact of the latest Somali fighting, and is working with partners in the international Somalia Contact Group to urge all Somali parties to cease further hostile action.
He said U.S. ambassadors in East Africa are making similar appeals to host governments, and said the United States does not believe the situation can be resolved on the battlefield.
The United States sponsored the December 6 U.N. resolution on Somalia, under which Ugandan troops would supply the core of the East African protection force.
The White House said President Bush telephoned Ugandan President Yoweri Museveni Tuesday to discuss Horn-of-Africa tensions and to thank him for supporting the envisaged mission.
The resolution eased the U.N. arms embargo against Somalia to permit introduction of the force, but was otherwise designed to discourage intervention by Ethiopia and by its regional rival Eritrea, which has given aid to the Islamic Courts.
Spokesman Gallegos said the United States continues to support the terms of Resolution 17-25, though its implementation has lagged and may be further set back by Ethiopia's open military role.
By David Gollust