BEIJING, Dec 28 (AFP) - The first expressway linking China and a member of the Association of Southeast Asian Nations (ASEAN) opened to traffic Wednesday, significantly reducing travel time, state media said. The 179.2-kilometer (110-mile) expressway begins in Nanning, the capital of south China's Guangxi region and leads to Vietnam's Friendship Pass at the border between Vietnam and Guangxi, the Xinhua news agency said. The expressway halves the traveling time between Nanning and the border to less than two hours, it quoted officials as saying. It now takes only five hours to travel from Nanning to Vietnam's capital Hanoi, officials said. With an investment of 3.7 billion yuan (456 million dollars), the eight-lane expressway is currently the most convenient overland passage linking China with ASEAN, according to Xinhua. The expressway is expected to help expand trade between China and ASEAN countries and promote the formation of the China-ASEAN Free Trade Area, which the two sides aim to develop by 2010. ASEAN has become China's fourth largest trade partner, with trade volume between the two growing 25 percent to reach 59.76 billion dollars in the first half of this year, according to China's ministry of commerce. ASEAN is the fifth largest export market for China and the fourth largest source for imports. The two sides initiated steps towards a free trade zone in 2002. The FTA will create the world's biggest free-trade zone, covering nearly two billion people. cs/sm