Ford Motors temporarily shut down several North American assembly plants on Monday because of parts shortages due to travel restrictions, after last Tuesday's attacks on the US, the BBC reported.

As a result, the automaker says, its third quarter earnings will fall short of its previous forecast.

Ford said the parts shortages stems from freight transportation restrictions, particularly in air transport and movement through border crossings.

Daimler-Chrysler has also reported parts shortages and production by General Motors and Honda has been scaled back in Canada.

Three Ford plants will be shut down from Monday and remain closed until 24 September while a fourth will shut for one day.

The automaker said its current production plans for the third quarter now require up to 820,000 vehicles, down almost 120,000 from its previous forecast.

DaimlerChrysler has said it is experiencing delays in deliveries of supplies of components and parts across the Canadian and Mexican borders following the attacks, a company spokeswoman said.

"Supplies are tighter because of congestion at the borders but we're operational. There are 12-15 hours of delays for trucks to get across the borders," she said.

"The parts are becoming more limited," she added.

She confirmed that the company shut down all US plants on Tuesday after the US attacks "in recognition of what had happened."

But normal production has resumed since Wednesday, she said.

BMW confirmed it shut down its US plant on Tuesday after the attacks "to allow workers to be with their families" but production resumed the following day.

A BMW spokesman said that 95 per cent of supplies, including engines, from Europe to the US plants are transported by ship and "about 5 per cent" by air freight but could not provide details on the impact of delays on production.