TIMELINE: Darfur conflict, peace efforts

(Reuters) - The U.N. Security Council has authorized up to 26,000 troops and police for Darfur and approved the use of force to protect civilians in Sudan's arid western region.

Here is a chronology of events in the conflict:

February 2003 - Two rebel groups rise up, saying government neglects arid region and arms Arab militia against civilians.

April 2, 2004 - United Nations says Darfur has become one of the world's worst humanitarian crises.

April 8 - Government, Sudan Liberation Army (SLA) and Justice and Equality Movement (JEM) rebels agree 45-day ceasefire. They later agree to foreign ceasefire monitors from the African Union (AU) and European Union.

May 5, 2006 - Sudan's government and SLA sign new peace deal. Rival SLA faction and the smaller JEM reject the deal.

August 17 - Britain and the United States introduce a Security Council resolution to send U.N. peacekeepers to Darfur. Sudan's ruling party rejects the draft resolution a week later.

August 31 - U.N. Security Council votes to create a U.N. peacekeeping force of up to 22,500 U.N. troops and police in Darfur, despite Khartoum's opposition.

January 10, 2007 - Sudan and Darfur rebels agree to a 60-day ceasefire and a peace summit sponsored by the AU and United Nations as steps towards stopping the violence.

Feb 27 - International Criminal Court's chief prosecutor names first two war crimes suspects in Darfur. Sudan says the ICC has no jurisdiction and later rejects arrest warrants.

March 31 - At least 65 people are killed in a cross-border raid by Sudanese Janjaweed militia in eastern Chad. Up to 8,000 civilians are driven from their homes.

April 2 - Unidentified gunmen kill five AU peacekeepers in Darfur, the deadliest single attack on the force since 2004. African Union says the help of U.N. troops is needed.

April 18 - United States and Britain threaten Sudan with sanctions and other punitive measures unless it agrees to accept a robust U.N. peacekeeping force.

May 29 - U.S. President George W. Bush imposes new U.S. sanctions on Sudan and asks for support for an international arms embargo to end what he calls genocide in Darfur.

June 12 - The AU says Sudan has agreed to the deployment, mandate and structure of combined U.N. and AU peacekeeping force.

Aug 1 - The U.N. Security Council authorizes up to 26,000 troops and police for Darfur and approved the use of force to protect civilians.