Sales by major automakers plummeted in the United States in June as consumers shied away from fuel-guzzling models in the face of 4 dollar per gallon petrol, monthly sales figures showed Tuesday, according to dpa. Monthly sales slid 19 per cent at General Motors, the nation's largest automaker from the year-earlier period, and the decline was an even steeper 28 per cent at Ford Motor Company, the companies said in statements. Toyota saw sales fall 21 per cent. By one measure sales were set to fall to their lowest level in more than 15 years, Bloomberg financial news reported. White House spokesman Tony Fratto told reporters that the drop in sales came as consumers changed their preferences in light of a weaker US economy and rising petrol prices. "That means that the automakers are going through a real transition," he said. "They're changing their vehicle fleets to try to respond to the tastes of customers out there. And so there's no question it's a tough time, not just for US automakers, but even for foreign automakers making cars in the United States are experiencing some of the same challenges." Sales also fell for Chrysler (36 per cent), BMW (11 per cent) and Acura (16 per cent). But sales figures rose 14 per cent at Honda, 13 per cent at Mercedes, 8 per cent at Kia and 0. 3 per cent at Volkswagen. Smaller, more fuel-efficient models continued to gain popularity even among automakers with overall declines.