The number of over-70s holding a driving licence has exceeded five million for the first time, new figures show.

Press Association analysis of DVLA data reveals 265 Britons over the age of 100 hold a licence, with four people aged 106 the oldest licensed drivers.

Driving licences held by people aged 70 and over (PA Graphics)(PA Graphics)

There has been a 15% spike in centenarians with licences since October 2015.

Once people reach 70 they must declare whether or not they are fit to drive every three years, without having to take a driving or medical examination.

(PA Graphics)(PA Graphics)

Concerns have been raised that some elderly people are continuing to drive when they are not fit to do so, while others may be giving up their cars too early and risk exclusion from services and activities.

Steve Gooding, director of motoring research charity the RAC Foundation, said: “Calls are routinely made for more testing of older drivers but most tend to have very good safety records and recognise their own limitations.

“However, with this huge demographic shift there will be challenges to maintaining safe mobility for all of us.

There are more than five million people aged over 70 with a driving licence (Anthony Devlin/PA)An ageing population presents a challenge for the motoring industry (Anthony Devlin/PA)

“Even where people are encouraged to hang up the keys for good in the interests of road safety, we must recognise the social and health problems that come with isolation.”

Out of the four key challenges ministers set out as part of their industrial strategy in November, one focuses on mobility and another on the ageing society.

The proportion of the UK population aged 90 and over has grown more rapidly than most younger age groups in recent years.

There were around 14,900 people aged at least 100 in 2016, according to the Office for National Statistics.