The African Union said Sunday it is ready to send peacekeeping troops to the restive eastern DR Congo, as leaders met at a biannual summit to discuss trouble spots and to vote for the bloc’s top job. AU Commission chairman Jean Ping told African leaders at the opening of the two-day summit the AU was “prepared to contribute to the establishment of a regional force to put an end to the activities of armed groups,” in DR Congo. No further details about the potential force were given at the meeting, attended by both DR Congo President Joseph Kabila and Rwanda’s Paul Kagame, who rejects accusations by U.N. experts and Kinshasa he supports the mutiny by Congolese troops. “The violence must end immediately, countries of the region ought to respect principle of non-interference,” U.N. deputy Secretary-General Jan Eliasson said. Rebels in eastern Congo threatened to view U.N. peacekeepers, of which Congo hosts the world’s largest contingent, as hostile forces unless the world body explains its role, in a letter to the Security Council Sunday. The threat comes only days after U.N. helicopter gunships bombarded several of the M23 rebels’ positions near Rutshuru in North Kivu province. The rebels allege that civilians were killed in the air raids, without providing an exact death toll. They say if the Security Council fails to explain the peacekeepers’ “real mandate,” they will assume that it has changed to make the U.N. an active partisan force, which would mean “to tell our forces to set up defenses against the U.N. troops, their infrastructure and staffers,” they said in the letter, obtained by The Associated Press. The renewed violence in the mineral-rich eastern DR Congo is a key focus of the summit as well as conflict elsewhere on the continent, including instability in Mali, and the ongoing crisis between Sudan and South Sudan. However, signs of improvement were seen in the dispute between Sudan and South Sudan, following fierce battles in April and March along their contested oil-rich border. Sudanese President Omar al-Bashir and Salva Kiir of South Sudan shook hands warmly, following their first face-to-face talks Saturday since the border fighting took them to the brink of war. Ping noted “with satisfaction the end to the fighting and advances made recently” in talks between Juba and Khartoum, who have been holding months of slow-moving AU-led talks to resolve a raft of contentious issues. For once, Ping noted positive changes in war-torn Somalia, praising the nations who had sent troops to battle the Al-Qaeda-linked Al-Shabaab, including Burundi, Djibouti, Kenya and Uganda in the 17,000-strong AU force, as well as Ethiopia. “The prospects for peace have never looked so encouraging,” Ping said. The contested AU leadership race is expected to dominate later proceedings. South Africa’s Nkosazana Dlamini-Zuma is challenging Gabon’s Ping, the current commission chairman, after neither won the required two-thirds of the vote at the last summit six months ago, leaving Ping in the post. Benin’s president and current AU chairman Thomas Boni Yayi warned that another failure to agree on a new head would damage the reputation of the 54-member body. “The current situation cannot drag on without undermining the running of the African Union and tarnishing its image,” Yayi told the summit. Newly elected Egyptian President Mohammad Mursi called on countries to “work toward electing a chairman ... on the basis of a consensus among all AU countries.” Analysts say unwritten tradition is that continental powerhouses do not run for the post – leaving smaller nations to take the job – and that South Africa’s decision to override this rule has sparked bad feeling. If no chair is selected at this summit, Ping – who has held the post since 2008 – could legally be asked to stay on as leader until the next summit in January 2013.