The Chinese envoy to Canada warned against letting politics interfere with its multibillion dollar takeover bid for Calgary-based Nexen Inc. (NXY) Last week, shareholders at the 40-year-old oil and natural gas company voted in favor of the proposal in what could be a landmark for a Canadian business. Lawmakers in Ottawa, however, have expressed reservations about Beijing's dominance in a market habitually tied to the United States. Though the Canadian government is keen to break its reliance on the U.S. markets, pressure from Beijing could force Ottawa into isolation.