Story highlights

French ferry workers started their industrial action Monday

Truck drivers forced to wait in sweltering heat because of disruption to ferry services

London CNN  — 

As southern England swelters in an unusual heat wave, thousands of truck drivers have been stranded along miles of a highway leading to the coast by a French ferry strike.

Authorities in Kent, south of London, implemented a plan called Operation Stack – in which freight traffic is held on the M20 motorway leading to the port town of Dover – after industrial action halted ferry crossings and temporarily closed the Channel Tunnel to traffic.

A limited ferry service is now operating again between Dover and the French port of Calais, the Port of Dover said. But it’s not known how long the holdups might continue on what is a key freight route between the United Kingdom and continental Europe.

Kent County Council said 2,000 bottles of water and 750 snack meals were handed out Wednesday – when temperatures climbed as high as 90 degrees Fahrenheit (32 degrees Celsius) – and that it had another 5,000 bottles and 200 meals to distribute Thursday.

MyFerryLink workers from the port of Calais started their wildcat industrial action Monday in response to the sale of the company, which is expected to threaten jobs.