Sudan has cut diplomatic relations with Chad after an attack on the Sudanese capital by Darfur rebels.

The government claims the attack was supported by Chadian President Idriss Deby.

The rebels fought Sudanese troops in a suburb of Khartoum in a bid to seize power but officials said the attack was defeated.

Sudanese authorities extended a curfew indefinitely and said troops were still hunting down rebels who were wandering the streets.

"These forces are all basically Chadian forces supported and prepared by Chad and they moved from Chad under the leadership of Khalil Ibrahim," President Omar Hassan al-Bashir said on state television.

Mr Ibrahim is the leader of the Darfur rebel Justice and Equality Movement (JEM) which attacked Khartoum state's suburb Omdurman after a lightning move through the country from the Chadian border.

"We are now cutting our diplomatic relations with this regime," Mr Bashir said in his comments, made after returning from the Muslim pilgrimage to Saudi Arabia.

It was the first time fighting had reached the capital in decades of conflict between the traditionally Arab-dominated central government of Africa's biggest country and rebels from peripheral regions.

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