As China and Central Asian countries contemplate a Silk Road economic belt, a trade group urged solving trade disputes and unbalanced investment between the two sides. Zhang Wei, vice president of the China Council for the Promotion of International Trade, said Friday that the organization has been working on such problems since Chinese President Xi Jinping proposed the belt and greater regional cooperation last year. Zhang urges removal of trade barriers that "constantly occur" in customs clearing, technical standards and service trade. A lack of uniform standards in inspection and quarantine, transportation, and an inefficient visa system have also hindered trade and investment flows, Zhang said. Zhang made the remarks at the 18th Investment and Trade Forum for Cooperation between East and West China and the Silk Road International Expo, which opened on Friday in Xi'an, capital of northwest China's Shaanxi Province. China is now the largest trading partner of Kazakhstan and Turkmenistan and the second largest of Uzbekistan and Kyrgyzstan, but Zhang said the trade is unbalanced and needs upgrading. China mainly imports fuel and ores from Central Asian countries, while exporting labor-intensive products like textiles and light industrial products. China's investment in the region also focuses on mining and construction, but neglects the manufacturing sector. Zhang suggested the two sides raise proportions of hi-tech, high value-added products and self-owned brands in their trade. They should also enhance collaboration in non-resource investment, he added. China and Central Asian countries are on the historical Silk Road that extended across Asia and connected China to Europe.