Investors are bracing for stock market falls after Canada and Mexico hit back against trade tariffs imposed by Donald Trump this weekend. Trading on the brokerage IG’s weekend markets indicate shares are likely to fall on Monday, after the US president signed an order on Saturday to bring in sweeping tariffs this week, a move that could prompt a trade war with some of the country’s largest trading partners. Technology stocks are expected to be hit, with the US’s Nasdaq index on track to fall 1.2% at the start of trading on Monday, according to IG. The official futures market…