Sudan and South Sudan are due to restart African Union-led talks in the Ethiopia on Tuesday in the first face-to-face meeting since bitter border fighting took the foes to the brink of all-out war. The talks aim to end hostilities and settling disputes after heavy border clashes scuppered an earlier round of negotiations. Fighting between rebels and Sudan’s armed forces has intensified in the past week following diplomatic talks which had stalled last month when Southern troops seized an oil field from Khartoum’s troops for ten days as Sudan launched repeated air strikes. Tensions remain high, but Southern President Salva Kiir stressed ahead of the talks that “amicable dialogue on the outstanding issues with Khartoum is the only option for peace,” according the South Sudan government website. The fighting has beset the country’s South Kordofan and Blue Nile border states since around the time of South Sudan’s secession last year. Late last week, Sudan said its forces had captured two areas from rebels in its Blue Nile state on the border with South Sudan following days of heavy fighting. Khartoum’s foreign ministry has said it will attend the May 29 talks and discuss a U.N. Security Council resolution that they resume dialogue on “critical” issues unresolved after the South gained independence. However, Khartoum on Sunday said it had complained to the U.N. Security Council over alleged “aggression” by the South, including alleged cross-border incursions, which it said broke a U.N. order to halt hostilities. Juba has accused Khartoum of continued air strikes on its territory. AU mediator and former South African president Thabo Mbeki has been shuttling between the two capitals in bid to ensure both sides attend the talks, which have already slipped from a U.N. Security Council May 16 deadline to start. “The AU is doing its utmost at all levels to make the resumptions of these negations a success, because there is no other way than peace - war cannot solve the problem,” AU spokesman Noureddine Mezni told AFP. Juba has said it is ready to comply with all articles in the U.N. resolution, while Khartoum committed itself to end hostilities but expressed reservations about some U.N. demands, which threatens sanctions for non-compliance. It was not clear when exactly on Tuesday the talks are expected to start, or for how long the talks are due to last. Mediators say the talks will focus on security issues, including ensuring both sides renew their commitment to earlier agreements to establish a demilitarized buffer zone scuttled by the weeks of fighting. Troops remain dug in at positions along the contested frontier, and both sides accuse the other backing rebel forces to destabilize the other. Mediators say that outstanding issues − including a bitter dispute over issues that include oil transit fees and contested border zones − are expected to be negotiated at later meetings. “The coming days are crucial...this will pave the way for a successful negotiation, this will give us confidence,” Mezni said. The southern nation broke away from Sudan in July under a 2005 peace deal that ended decades of civil war, but the division left tens of thousands of fighters who had sided with the South on the northern side of the border. But tensions soon flared again over a series of unresolved issues, including the border, the future of disputed territories and oil.