The mighty Mekong river flows for 4,800km and is the lifeblood of the diverse regions it nourishes along the way. But while this vast stretch of water provides a vital link between the six countries benefiting from the natural resources it provides, co-operation between them on trade and development has not always been easy to achieve. It is therefore encouraging to see progress being made at the conference that ended yesterday in scenic Dali, in Yunnan province, attended by trade and finance ministers from China, Thailand, Vietnam, Myanmar, Laos and Cambodia. The scope covered by the Mekong Sub-region Economic Co-operation Programme is broad, taking in the building of railways and roads, the relaxing of impediments to trade, as well as sustainable development projects and attempts to crack down on drug trafficking. But it is in the area of trade that the most significant advances have been made. A cross-border agreement that will pave the way for the swifter and easier movement of goods around the region has now been entered into by all six nations, with Myanmar the last to sign. The pact will simplify customs checks and further road and telecommunications links. Work is also continuing on a key expressway project that will run all the way from Kunming to Singapore. And plans are also afoot to put in place a single visa arrangement for visitors from outside the region, to help boost tourism and investment. The projects are being aided by huge loans from the Asian Development Bank, which has pumped around US$3 billion into the region over the past decade in a bid to further economic ties. The six countries concerned are linked not only by the river, but also by strong cultural and historical ties. But suspicion and rivalry has long stood in the way of co-operation among the nations, which all face challenges tackling poverty. In recent times, fears that greater integration will lead to China - which has the biggest economy - dominating the region have been paramount. But there were signs at this week's conference that those concerns are gradually being overcome. Both Chinese leaders and Asian Development Bank officials have gone out of their way to convey the message that China's economic strength can, through closer co-operation, benefit the region as a whole. It is understandable that the Mekong countries - particularly those in the lower reaches of the river who depend more heavily upon it - will want to guard the valuable natural resources the river provides. But a co-ordinated, consensus-driven approach will better serve the interests of all. Easing trade restrictions and developing closer links can provide the foundations of a common market for the region. Through trade, it is hoped, differences can be settled and the benefits seen by the people of these countries.