Tight budgets mean a likely increase in the number of cars being driven without current MOT certificates, according to Halfords.

In a survey of 2,006 motorists it found that almost one in five whose car's MOT test falls in March don't believe they cannot afford it, and two thirds of those will continue to drive the car anyway, breaking the law.

Halfords, which opposes ongoing Government proposals to change the MOT test requirements, warned this could result in 400,000 untested vehicles on UK roads.

It could be an opportunity for established garages to heavily promote their ability to let consumers spread the costs of car repairs over several months, through providers such as Bumper and Payment Assist.

Halfords chief executive Graham Stapleton said: 'The data shows that March is set to be the worst month we have ever seen when it comes to cars on our roads without an MOT."

The research found those aged 18 to 24 are most likely to not be able to afford their MOT (22%) whilst also being most likely to drive their vehicle anyway (84%.)

Of all those unable to afford their next MOT, 66% say they simply do not have enough money and will have to spend funds elsewhere.

A quarter of those who plan to avoid their MOT entirely (23%) said they previously got away without having one, and nearly half of those who plan to continue driving regardless (47%) say it is so they can get to work - which does not pay enough to afford the test.

It is illegal to drive a car without an MOT unless the driver can prove they are driving to an appointment at a test centre.

The Department for Transport has a consultation under way currently on proposals to change the UK's MOT requirements, which have remained the same for 50 years.

It wants to hear industry views on its options, which include changing the first MOT test from a light vehicle's third year since registration to its fourth or even fifth.