Suzuki Motor and Mitsubishi Motors may have to pull out of the US market because of plummeting sales of new cars in a market which has now fallen behind China, analysts said.

Both Japanese carmakers have been selling cars in North America for 25 years (though Mitsubishi entered Canada only in 2002 and Mexico in 2003) but Suzuki reported a 78% drop in unit sales in June, pushing its first-half decline to 60% over the same period last year. Mitsubishi was down 51% year-on-year.

Yuuki Sakurai, chief executive of Tokyo-based Fukoku Capital Management, told Bloomberg News both carmakers should withdraw from the US. “It’s time for them to decide whether they pay a high price to continue business there or stop the bleeding,” he added.

Alexander Edwards, head of auto research for San Diego-based Strategic Vision, said: “Both are struggling with getting customers to initially even consider them. Currently, they rank in the bottom five of 35 brands Strategic Vision tracks. To reverse that, both need to boost their US marketing budgets.

“We’re not talking about a one-time investment, but a consistent, sustained effort,” he said. “If they’re looking for a quick fix, continuing in the market will be tough.”

However, earlier this month Mitsubishi Motors president Osamu Masuko said the company would never give up the US market, adding that he believed North America would return to being the world’s biggest market.

Suzuki sold 84,865 vehicles in the US last year, a 17% fall. Mitsubishi sold 97,257 vehicles, down 25%.

Both companies also have North American assembly plants that are under-utilised. Suzuki’s CAMI Automotive joint venture with GM in Ontario, Canada, stopped making Suzuki’s XL7 SUV this year and no new model has been announced. GM makes Chevrolet Equinox and Pontiac Torrent SUVs at CAMi, and plans to make the GMC Terrain crossover at the Canadian plant. Cami’s output was down 78% this year according to Automotive News.

Production at Mitsubishi’s Normal, Illinois, plant, was down 83% this year but a company spokesman said it was not planning to close the plant. Bloomberg noted that Mitsubishi had not announced replacements or additions to its current lineup of midsize and compact cars and SUVs in more than a year. The company hopes to sell the i-MiEV electric car in the US by 2010, after introducing the model in Japan this month.

Others to have withdrawn from the US include the former British Leyland/Rover Group, Rootes Group/Chrysler UK, Fiat, Alfa Romeo, Peugeot, Citroen and Daihatsu.