Smart motorway plan for M3 in Hampshire is 'dangerous'

Mary Creagh, the party's transport spokeswoman, launched a surprise attack on the 'smart motorway' measures announced earlier this year.

The scheme will add an extra lane in both directions on a short section, by allowing motorists to drive on the hard shoulder normally set aside for breakdowns.

And it will cut the speed limit to 60mph between 7am and 7pm each day, in order to avoid worsening air quality levels and to try to meet European Union rules on pollution.

The Highways Agency is staging consultations this month, planning the changes for a three-mile section of the M3 between junction 4, near Farnborough, and junction 3, in Surrey.

The 'smart motorway' scheme has already been introduced on sections of the M1, M4, M5, M6, M42 and M62.

But, speaking with the Daily Echo at Westminster, Ms Creagh said: “I have a concern about the safety of that.

“This is a cheaper way of widening motorways - hard shoulder running and slowing down speeds to 60 - but there are air pollution issues.

“You end up with air pollution and, potentially, more motorway accidents and you've got no refuge. Everything has a potential benefit, but also a potential cost.”

The Highways Agency has already began installing CCTV cameras on the M3, alongside work to strengthen the hard shoulders and slip roads.

It says the changes will “see motorists have more reliable and free-flowing journeys and save time going in and out of London”.

Ms Creagh was asked how Labour would tackle traffic jams on the M3 and M27, among the country's busiest motorways.

She all-but ruled out tolls, or any form of 'road pricing', arguing tolls were only likely on river crossings.

Ms Creagh said the only long-term solution were cleverer ways to shift motorists onto public transport, to ease the pressure on motorways.

And, asked about the M27, she said: “You get traffic jams between 6 and 9 in the morning and 4 and 7 in the evening - the rest of the time traffic flows freely.”