Both sides signed two accords - humanitarian and security protocols - on Tuesday at the talks being hosted by the African Union (AU) in the Nigerian capital of Abuja.
Agricultural Minister Majzub al-Khalifa inked the deal on behalf of the Sudanese government at a ceremony hosted by the current AU chairman, President Olusegun Obasanjo of Nigeria.
Political leaders of the rebel Sudanese Liberation Movement (SLM) and the Justice and Equality Movement (JEM), Minni Arkou and Muhammad Tugod, also signed the documents.
"You can call this the beginning of a good future. You can describe it as the beginning of peace, security, progress and development in Sudan. You can call it the beginning of friendship and harmony," Obasanjo said.
The Darfur conflict has made
"Now we are beginning to go towards peace. We are sending a new signal to the whole world," al-Khalifa said.
AU officials said that both sides would be held accountable for future ceasefire violations.
"These documents will not be worth the paper they are printed on if they are not scrupulously observed," said Obasanjo.
The breakthrough was made possible after the Sudanese government dropped its objection to clauses in the security deal committing it to end military flights over Darfur and to disarm the Janjawid.
AU mediators drew up the protocol to demilitarise the 20-month-old conflict ahead of future talks to find a lasting political solution.
It commits the warring parties to halt all offensive operations and to fully cooperate with the 3250-strong AU truce-monitoring force.
And in a separate humanitarian deal, both parties agreed to improve the safety of Darfur's 1.5 million displaced civilians by guaranteeing access to aid agencies and pulling their forces back from around refugee camps.
Fighting erupted in Darfur, a parched and impoverished region in Sudan's remote and rural west, in February last year when the JEM and SLM launched an armed revolt against the Khartoum government.