CBOT soybean futures fell on profit-taking after hitting a 20-month high. Recently driven by improved biodiesel demand prospects, U.S. soybeans have been trading at elevated levels. On Thursday, the U.S. government's plan to reallocate at least 50% of previously exempted biofuel blending obligations to large refineries further boosted the market. However, tariff uncertainties and doubts over U.S. soybean export prospects weighed on the market, weakening export expectations. The USDA's weekly export sales report released on Thursday showed that net U.S. soybean export sales for the week ending February 19 were 407,100 metric tons, at the lower end of market estimates. Market attention is focused on whether the U.S. president can visit China by the end of March. In the short term, U.S. soybean futures are expected to maintain a high volatile range.