A car insurance website has warned of the risks of driving while unfit as Dominic Cummings admitted going for a "short drive" to test his eye sight after falling ill.

In a press conference on Monday, Mr Cummings - Boris Johnson's chief adviser - said he went for a 30-mile drive in Durham to ensure he could drive safely after showing symptoms of coronavirus, with his wife worried his illness might have affected his eyesight.

Mr Cummings said that after agreeing with his wife that he could drive safely, they decided to drive back to London.

Now, MoneySuperMarket has said there can be "very serious consequences" if motorists are struggling to see behind the wheel.

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Dave Merrick, car insurance spokesperson at MoneySuperMarket, said: “If police suspect you to be struggling with your vision while driving, they can pull you over and conduct an eye examination. If you fail, this could result in you losing your licence. Prosecution is also a possibility if you have an accident as a result of poor vision.

“It can also have a significant impact on your finances. For example, failure to inform the DVLA of issues with your vision can result in a £1,000 fine. And if your decision to drive goes against doctors’ orders, you could also risk voiding your car insurance policy.

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“If you suspect that the difficulties you are having with your eyesight render you unfit to drive, our advice is that you should avoid getting behind the wheel of a car and ask someone else to drive or look for alternative sources of transport. You should also make the DVLA aware of any eyesight issues you have."