 An African Union summit opened on Monday with the stage set for a battle over Sudan's determination to assume the chair despite fierce criticism of continuing bloodshed in its Darfur region. Sudan was adamant it should get the chairmanship, promised a year ago, despite a chorus of demands from rights organisations and Western governments that it be snubbed because of abuses in Darfur, where the the United States says genocide has occurred. Sudanese Foreign Minister Lam Akol told Reuters: "I don't expect responsible leaders of the AU to change their position because there are some rights groups outside the AU pressuring them. I think they are beyond pressure." The chairmanship was promised to Sudanese President Omar al-Bashir a year ago when he was passed over for the post because of the violence in Darfur, which experts estimate has killed 200,000 people and driven 2.5 million from their homes. Critics say that far from abating, the violence has worsened in the last year and government-backed Arab militias have killed thousands. Bashir has repeatedly blocked deployment of UN peacekeepers to bolster an overstretched African Union military mission of 7,000 soldiers and monitors. In an opening speech at the summit, the AU's top diplomat, Alpha Oumar Konare, accused Sudan of attacking Darfur civilians. "We appeal to the government of Sudan to stop attacking and bombarding Darfur and instead restore peace," he said. Rights group Amnesty International said in a statement on the eve of the two-day summit that the AU would undermine its credibility if it gave the chairmanship to Bashir while abuses continued in Sudan's vast Western region. Chad, whose relations with Sudan are severely strained after the Darfur conflict spilled over their border, has vowed to withdraw from the AU if Bashir gets the chair. Asked at the summit opening what he would do if the chair went to Sudan, Chad President Idriss Deby said: "This is not a foreseeable step that would be taken by the African Union." Egyptian Foreign Minister Ahmed Aboul Gheit told reporters: "The Egyptian position is that there is a decision to give Sudan the chair and that needs to be implemented unless the summit decides otherwise." But he expected as big a struggle over Sudan's candidacy as a year ago. Nigerian President Olusegun Obasanjo told reporters: "I think we will have an easier solution to the question of the chairmanship than we did last year. The decision has not been made." Diplomats said moves were under way to promote Tanzanian President Jakaya Kikwete as an alternative to Bashir. They said Western governments were lobbying in favour of Kikwete. "(The AU) is one of the great success stories in international relations and diplomacy and it can be lost in half an hour. That's what the AU needs to weigh up," British Africa minister David Triesman told Reuters before the summit. An AU committee of seven "wise men", including Obasanjo, will discuss the Sudan issue on Monday and then present recommendations to the full summit, delegates said. The Addis Ababa meeting is also due to discuss raising a peacekeeping force for Somalia to replace Ethiopian troops, unrest in Guinea and climate change, as well as the AU military mission in Darfur, but diplomats say much of the debate will be overshadowed by Sudan. Delegates said opposition to Sudan was rising among the AU governments. "How can you ask someone who is dealing with their own internal conflict to deal with all the other issues going on the continent? The leaders are taking this into account and a solution will be found," one African delegate said.