A British car engine factory has been forced to halt its production line as a direct result of a strike by militant French ferry workers.

The Toyota plant has been starved of vital parts because lorries full of key components have been stranded by the four-day blockade of Calais, which is estimated to have cost the UK economy £1billion.

Toyota confirmed it was ‘not currently manufacturing’ on its assembly line in Deeside, North Wales, where it builds petrol engines for the new Avensis and Auris models.

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Toyota has announced it has halted its production line, pictured, due to shortages caused by the blockade

Thousands of trucks are still waiting to cross the channel following the Calais dispute and disruption

Operation Stack caused chaos on the M20 in Kent as the disruption in Calais spread to south east England

Although the latest blockade was lifted on Wednesday night, the backlog of delays is expected to last until Sunday on both sides of the Channel, while there is a threat of even more disruptive industrial action over job losses.

Hauliers estimate 5,000 lorries were stranded in Britain with another 3,000 on the French side. As engine production stopped at the Deeside factory at 10am yesterday, 70 affected shift workers were found alternative duties or allowed voluntary leave. The Toyota factory employs 522 staff, of whom 130 work on the assembly line.

The plant builds 440 engines every day, of which half are sent to the firm’s car assembly factory at Burnaston, Derbyshire, with the remainder exported to Turkey and South Africa.

Burnaston is still operating but with ‘a small reduction in planned overtime’.

÷Theresa May has pledged to put more money into holding back thousands of migrants camped in Calais amid warnings from MPs that a driver could ‘soon be killed’.

During crisis talks with her French counterpart, the Home Secretary said Britain and France must work together to stop people-smuggling gangs based near Calais.

She also urged the French to take measures to stop migrants leaping on to vehicles stuck in queues caused by strike action.

On the UK side of the channel, truck drivers were given bottles of water to cope with the extreme heat