TIMELINE - Tensions between Sudan and Chad

(Reuters) - Sudan has accused neighbouring Chad of backing rebels who attacked the capital Khartoum at the weekend and has cut diplomatic relations.

Here is a chronology of recent Chad-Sudan tensions:

Jan/Feb 2004 - Thousands of refugees from Sudan's Darfur region arrive in Chad fleeing government bombings and raids by Arab Janjaweed militias.

April 9 - Chad brokers a ceasefire between the Sudanese government and two Darfur rebel groups.

April 11, 2005 - Chad suspends mediation, accusing Sudan of supporting Chadian rebels. It returns to mediation after promises from Khartoum that it would act against the rebels.

December 18 - Chad says its forces killed about 300 rebels after they launched a failed offensive on the border town of Adre. Sudan denies involvement.

Feb 8, 2006 - Chad and Sudan agree to put an end to their dispute at a meeting in Libya.

April 13 - Chad government forces fight off attack by rebels on the capital N'Djamena. Several hundred people killed. Deby breaks diplomatic relations with Sudan the next day.

Aug 8 - Chadian President Idriss Deby and Sudanese President Omar Hassan al-Bashir agree to restore ties.