Cars and auto parts imported by the US from the EU face a tariff rate of 27.5%, but the Trump administration has agreed to lower this to 15% if the EU reduces its levies on US goods. Winkelmann told CNBC on Tuesday that the Italian sports car company's customers want "security" and "stability." "Some are waiting because they want to be sure that this is the final number that is going to be in place," Winkelmann said. "Others are fine with it, or we will have negotiations."