US new light vehicle sales likely rose in May to close to a 10m unit annualised rate, supported by sales at closing Chrysler dealerships in the past week, Ford's chief sales analyst has said.

That result would represent a rise from the roughly 9.3m sales rate in April, but does not yet reflect a confirmation that the US auto industry sales downturn has begun a recovery, George Pipas said in an interview with Reuters. It would also be the highest rate since January's 9.8m.

"The circumstances surrounding this month's sales results are such that the elevation off of this floor that we had been operating under is taking place mostly at Chrysler dealerships," Pipas said.

Chrysler, in bankruptcy protection since 30 April, has been closely watched by investors and government officials to see whether its sales would hold up.

GM is widely expected to file for bankruptcy protection later on Monday to complete a similar sale process.

"We could see volatility, we could see really distressed pricing," Pipas said. "I think we won't have a true picture for some time as to what is happening with industry sales."

Ford expects to report a retail market share increase in May from a year earlier, following the trend in recent months, while total sales will be down year over year along with other automakers, Pipas told Reuters.

He said industry sales had run at about the same rate as from January to April for the better part of May. The automaker has not changed its position on expectations that industry sales would begin to pick up in the second half of the year.

"We are in the camp that there is going to be a recovery, but the question as to whether it started in May or whether (May sales) are due to something else will have to be assessed," Pipas said.

Most other automakers had a relatively constant rate of sales in May, Pipas said.

Reuters noted that Chrysler CEO Bob Nardelli had told bankruptcy court on Thursday that the 789 dealerships that Chrysler plans to terminate on 9 June had sold 4,000 vehicles at retail and transferred 15,000 to other dealerships to the end of last Wednesday.

A spokeswoman later told the news agency the closing dealerships had accounted for 26,000 vehicles to the end of Thursday, but she could not give a breakdown on where the vehicles went.