A third of Britons are unsure of what their motor insurance covers because they have failed to read their policies, a study has shown.

Car insurance firm Norwich Union has found that just under 40% of drivers do not know what is covered under their motor insurance policy, with 33% stating that they had not bothered to read their documents to find out.

Additionally, 38% of respondents were clueless as to when their car insurance would expire.

Darren Cornish, head of customer experience at Norwich Union, said: "Our research highlights a lack of understanding about insurance. Customers who do not know what they are covered for could face disappointment when claiming if their expectations are not met - something which could be avoided if they understood what is in their policy before they need to claim."

More than a third of motorists thought their car insurance would cover them if they left the keys in the ignition and the vehicle was then stolen, the results showed.