Beijing has postponed a visit to the US by its senior trade minister, during which officials had hoped to kick-start the faltering World Trade Organisation negotiations. Confusion surrounds the postponement of next week's scheduled visit by Trade and Economic Co-operation Minister Shi Guangsheng. US officials have been told Mr Shi is ill and unable to fly, although one Washington source close to the talks doubted the official reason. He said Mr Shi's absence might be connected to internal Beijing politics and impending personnel changes in the Government. Chinese Embassy spokesman Yu Shuning said he did not know why the trip had been put back. The setback comes as feelings in Washington are beginning to run high, especially on Capitol Hill, over Beijing's failure to correct its trade surplus with the United States, which is running near US$50 billion (HK$386.8 billion) for the year. The central focus of the visit was due to be the annual meeting of the Joint Commission on Commerce, a high-level Sino-US group which promotes trade. Mr Shi was scheduled to hold talks with Commerce Secretary William Daley and US Trade Representative Charlene Barshefsky, among others. High on Beijing's talks agenda is Washington's proposed ban on the raw wood crates used by China to export much of its goods, a measure the Americans hope will stop a tree-destroying Asian beetle taking hold in the US. The postponement is likely to lead to further speculation in Washington that Beijing has decided to shelve for at least a year any serious discussion on its entry to the global trade organisation.