Image copyright Gov.uk Image caption Some smart motorways use the hard shoulder at all times while others use it during busy times

Smart motorways are to be reviewed following concerns over driver safety, the transport secretary has said.

Grant Shapps told MPs: "We know people are dying on smart motorways".

He said recommendations are expected "in a matter of weeks" to ensure all motorways are "as safe as they possibly can be".

Earlier this week, Highways England boss Jim O'Sullivan warned "dynamic" smart motorways are "too complicated" for drivers.

Mr O'Sullivan said he did not think he would build any more dynamic smart motorways because too many motorists do not understand them.

There are two types of smart motorway in the UK: The first is where the hard shoulder is opened to traffic when it is busy, and the second is where the hard shoulder is open all the time.

They already account for about 400 miles of England's roads, including sections of major motorways like the M1, M6, and M62.

They were created to ease congestion, using computers to monitor the roads and change speed limits.

Critics have called for smart motorways to be scrapped over safety concerns and several deaths.

Eight-year-old Dev Naran was killed on the M6 last May when a lorry struck his grandfather's Toyota while it was pulled up on the hard shoulder, which was in use.

Image copyright Family handout Image caption Dev Naran sustained a fatal head injury in the crash

Speaking to MPs on the Commons Transport Select Committee, Mr Shapps said: "I have asked my department to carry out at pace an evidence stock-take to gather the facts quickly and make recommendations."

He said his department would lead the review "because some of the statistics have been difficult to understand, and we know people are dying on smart motorways".

He added: "Understanding whether they are less safe, the same or safer - it turns out not to be as straightforward as members might imagine - I want all of those facts and recommendations that can be put into place to ensure that all of our motorways are as safe as they possibly can be.

"I will get this done in a matter of weeks."

Derek Jacobs, 83, was killed when his car was hit after it stopped on a smart motorway section of the M1 in Derbyshire.

His death came six months after another woman was killed after a breakdown on the same section of road.

Jason Mercer, 44, died on the M1 near Sheffield, where the hard shoulder is an active lane.

He was involved in a minor collision but when he got out his car to exchange details he and the other driver were hit by a lorry. Both died at the scene.