Beijing is hopeful about its next round of trade talks with the US, China's vice minister for commerce said Saturday, after revealing that top negotiators had tried to hammer out a deal over burgers and eggplant chicken. China and the United States have been locked in a bruising trade war since last year, imposing tit-for-tat tariffs on more than USD 360 billion in two-way trade, which has left global markets reeling. Top-level negotiators have met thrice in an attempt to reach an agreement ahead of next week, when additional tariffs could be levied on Chinese goods entering the US as a truce period expires. "When you ask about the prospects for the next Sino-US economic and trade consultation, I feel that there is hope," Vice Minister for Commerce Wang Shouwen told journalists at a press briefing on the sidelines of China's National People's Congress. He added that Beijing's top economic official Liu He and US Trade Representative Robert Lighthizer held talks over a packed lunch of burgers and eggplant stir-fried with chicken - a common Chinese dish - in Washington last month. "Vice Premier Liu ate a beef burger, and Lighthizer ate eggplant and chicken (with rice)," Wang said. "Throughout the consultation process, there was coffee and tea. but both drank plain water." "This was to find common ground," he added. Chinese Commerce Minister Zhong Shan had on Tuesday said the negotiation process was very "difficult and taxing" with "lots left to do", but that breakthroughs had been made in several areas. But there have been conflicting comments from Washington and Beijing on the negotiations. Donald Trump on Friday said he remains optimistic but will not sign a pact unless it is a "very good deal", and a top economic advisor said the US president could walk away from a bad deal. Commerce officials also said a foreign investment law - widely expected to be passed by China's rubber-stamp parliament next Friday - will allow foreign companies to take part in government tenders. Only 48 sectors remain on a "negative list" where foreign investment is either prohibited or requires special approval, Wang told journalists. "The (whole process) is open and provides important legal protection for foreign investors." Aimed at assuaging concerns about China's business environment for foreign firms, Beijing sees the law as a tool to attract more foreign investment as its economy slows. The bill will ban the illegal transfer of technology and "illegal government interference" in foreign businesses, a key complaint from Washington.