As ambassadors to the United Nations met in New York, Lieutenant-General Alex Harley, Deputy Chief of the Defence Staff (Commitments), was heading for urgent talks in Washington.
The first British reconnaissance teams, including 40 specialists from various branches of the armed forces, leave for Africa today.
Michael Portillo, Secretary of State for Defence, told the Commons: "We must prepare ourselves now for action." He said British troops would not go if he did not think the mission was "achievable" and said the rules of engagement still needed to be established.
But a large British force, probably headed by 5th Airborne Brigade headquarters, is expected to leave very soon.
The international force will be deployed under Chapter Seven of the UN Charter, which sanctions action by land, sea and air to restore peace between belligerent parties. Although it will focus on humanitarian aid, it will be able to act in a much tougher fashion than UN troops in Bosnia were able to.
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