The African Union says Sudan must stop the aerial bombardment of South Sudan and has called on both countries to cease hostilities immediately. A statement from the AU Peace and Security Council says the two countries must withdraw their forces from the disputed border region and keep their troops within their borders. The statement released after a council meeting late Tuesday, said that the two neighbors should also stop issuing inflammatory statements and propaganda that could escalate the conflict. South Sudan's president said Tuesday that Sudan has declared war on his country following the north's repeated bombing of the south. Sudan and South Sudan have been drawing closer to a full-scale war in recent weeks over the unresolved issues of oil revenues and their disputed border. Meanwhile, South Sudan's president would cut short his visit to China due to “domestic issues”, a Chinese official said Wednesday, as violence between the world's newest nation and Sudan intensified. The curtailment of South Sudan President Salva Kiir's visit to China was confirmed by Wu Bangguo, nominally the second-ranking Chinese leader, during a meeting between the two men in Beijing. “It is unfortunate that you have to shorten your stay in China due to domestic issues and are not going to Shanghai,” Wu told Kiir as the two men began talks in the presence of journalists. Neither of the two made further reference to the decision before reporters covering the start of their meeting were ushered from the room. Chinese foreign ministry spokesman Liu Weimin had earlier told reporters that Kiir, who arrived in China late Monday, had cancelled a scheduled visit to Shanghai but did not give a reason. Kiir's visit to China had been scheduled to continue to Saturday.