|The Justice and Equality Movement (JEM) leaders called al-Bashir's ultimatum a 'declaration of war' [AFP]
Sudan's government has withdrawn from peace talks with Darfur rebels, but it insisted that it is still committed to the peace process.
Members of the government delegation announced the decision on Thursday at a summit in the Qatari capital, Doha.
"We have just informed our mediators that our delegation will be departing on Friday," Ghazi Salaheddine, the Sudanese government's special adviser on Darfur, told a news conference.
"The delegation will leave because it has nothing to do, but that does not mean we withdrew from the peace process, and the mediators have promised us a document" on a possible agreement in Darfur, he said.
Al Jazeera's Mohammed Adow, reporting from the Sudanese capital, Khartoum, said the government has said it is still willing to consider any draft document that might come from the Qatar mediation team, even without its delegation being present in Doha.
"[But] at the moment it looks as if the government has withdrawn and says any more negotiations with the Darfur rebels will have to take place inside the region," he said.
"The government seems to have begun implementing its new peace plan for Darfur. Among other things, the plan calls for engaging with the local community. It deemphasises negotiations with the rebels, who the government blames for past failures.
"All this now has been rejected by the rebels and the stage seems to be set for an uptick in violence in the troubled region."
'Declaration of war'
Thursday's withdrawal came a day after Omar al-Bashir, the Sudanese president, said he would recall the delegation from the talks, which have been ongoing for almost two years. He said the government would organise its own negotiations if no agreement was reached this week.
His comments prompted an angry response from one rebel group in the country's war-torn western region - the Justice and Equality Movement (JEM) - which called the remarks "a declaration of war".
Ahmed Hussain Adam, a JEM spokesman, told Al Jazeera that al-Bashir wants only a military solution.
"Al-Bashir is carrying out a lot of military offensive action on the ground against our own people," Adam said.
"When he declared that he is abandoning the Doha process, it is clear that this was a declaration of war.
"So we don't have options other than to defend ourselves and defend our people on the ground. We don't believe that there will be a military solution to this, there is only a political solution to this problem Al-Bashir has to have the political will."
The Doha peace talks suffered a major blow earlier this week when Darfur rebels clashed with Sudanese government troops three days after announcing they had resumed ceasefire negotiations.
The Sudanese government said its forces killed 40 rebels in the fighting in northern Darfur and that two of its soldiers were also killed and 13 others injured.
Deadly violence in Darfur since December 10 has displaced around 32,000 people, according to UN estimates.
Darfur has been gripped by a civil war since 2003 that has killed 300,000 people and displaced another 2.7 million, according to UN figures. Khartoum says 10,000 people have died in the conflict.