The Icelandic volcanic ash cloud has forced carmaker Nissan to temporarily halt several production lines at two of its Japanese factories with the loss of 2,000 vehicles.
The stoppage was necessary because of a lack of air pressure sensors for tyres that are fitted to its Murano, Rogue and Cube models sold in the United States.
The sensors are normally flown in from Ireland where they are made.
And carmaker BMW said it is having to partially halt production at three of it plants in Germany this week because parts have not arrived due to cancelled cargo flights.
The assembly of around 7,000 vehicles will be delayed.
It had already slowed production at its US plant in South Carolina because flight restrictions in Europe have hampered deliveries of transmissions and other components for the X5 and X6 models built there.