The president of Chad has cut diplomatic ties with Sudan, which he accuses of backing rebels trying to overthrow him.
President Idriss Deby has also threatened to expel 200-thousand Sudanese refugees, unless the international community stops what he called Sudan's efforts to destabilize his country.
Mr. Deby spoke in Chad's capital N'Djamena today (Friday), one day after his forces fought off a rebel attack in the city's east. Chadian officials say at least 350 people were killed in the fighting, most of them rebels.
Sudan's Foreign Minister Lam Akol says his country has nothing to do with the events in Chad.
However, the Central African Republic said on Friday it will close its border with Sudan. The C.A.R.'s foreign minister Jean Paul Ngoupande condemned what he called Sudanese aggression.
President Deby has declared victory over the rebels, who assaulted the capital after a week of attacks in other parts of Chad.
Leaders of the rebel group the United Front for Change have vowed to continue their campaign to topple Mr. Deby. Chad's government calls the rebels mercenaries hired by Sudan.
The United Nations has evacuated all non-essential staff and the personnel of various aid agencies from N'Djamena. The U.N. World Food Program heads up efforts to feed the Sudanese refugees, who fled Sudan's war-torn Darfur region.