LONDON — European markets looked set to begin the new week in negative territory as investors continue to monitor developments in the Middle East and a potential renewal of transatlantic trade tensions. Stoxx 50 futures were expected to open 0.32% lower, with France's CAC 40 sliding almost 0.1%, Germany's DAX falling 0.27% and the Italian FTSE MIB down 0.31%. The U.K.'s FTSE 100 is closed for the early spring bank holiday. European automakers were seen between 1.2% and 2.2% lower in pre-market trading after U.S. President Donald Trump said Friday he would increase tariffs on cars and trucks from the European Union to 25%. The European Commission said it was keeping its options in terms of its response. The threat comes despite a Supreme Court ruling in February striking down large parts of Trump's tariff agenda. Meanwhile, President Trump also unveiled a new plan to "free" ships that have been unable to pass through the Strait of Hormuz.…