The RAC warned that journeys on popular routes could take twice as long as usual, as the bank holiday weekend leads into a two-week holiday for many schools.

Trains are also set to be stopped as Network Rail carries out engineering works on the West Coast Main Line - which stretches from the capital to Scotland - between London Euston and Milton Keynes.

That stretch of rail will be closed between Good Friday and Easter Monday, with disruption also expected in Glasgow and Huddersfield.

Laurence Bowman, Network Rail's network strategy director, said there is "never a good time to do the work we need to do", but explained that a lower number of commuters over the bank holiday weekend gives them "the opportunity to do major work we couldn't do in a normal weekend".

"We've got 493 different pieces of work taking place this Easter, most happening overnight," he added, "including laying over 8,000 metres of new rail and putting down over 40,000 tonnes of new ballast to support the tracks."

RAC spokesperson Alice Simpson also warned it "could be carmageddon" over Easter and said heavy traffic and "lengthy queues can be expected along routes to the usual hotspots".

Inrix transportation analyst Bob Pishue also said that "drivers should be prepared for longer journeys than normal throughout the entire weekend".

Worst day for driving

A survey commissioned by the RAC and Inrix found that 2.6 million journeys are planned on Good Friday, with around 2.3 million trips expected for both Easter Saturday and Sunday.

Another two million trips are expected on Thursday and Easter Monday, and a further 3.3 million journeys are due with no clear starting date, making for a total of around 14.5 million journeys.

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Inrix predicted that the worst of the traffic is expected between 2pm and 7pm on Thursday, when holiday journeys are set to mix with regular commutes.

It added that the busiest route is set to be the western section of the M25 between the M23 for Gatwick and the M1 for Hertfordshire where journeys from 4pm are tipped to take more than two hours, more than twice as long as usual.

The M5 southbound between Bristol and Taunton, and the M3 between the M25 and the south coast are also likely to be congested, according to Inrix, with estimated journey times more than double what they normally are.

The survey, from research company Find Out Now, polled 2,136 UK adults.