BEIJING, Aug 28: China and the United States stressed the positives in their complex relationship on Friday during meetings between U.S. National Security Adviser Susan Rice and Chinese officials ahead of a U.S. visit by Chinese President Xi Jinping next month. While the world’s two largest economies have important mutual interests, like trying to rein in North Korea’s nuclear program, deep disagreements exist over everything from Internet security to China’s claims in the South China Sea. “We have seen our bilateral relationship evolve and strengthen in recent months. And we have found areas of broadened and deepened cooperation that we are certainly looking forward to building upon,” Rice told China’s top diplomat, State Councillor Yang Jiechi, who outranks the foreign minister. “At the same time, we have been able to discuss frankly our differences, which we both acknowledge need to be addressed effectively.” Yang said that both countries had cooperated closely over the Iran and North Korean nuclear issues.