Calls for emergency stopping lanes to be reinstated on smart motorways due to safety concerns have been rejected by the Transport Secretary.
Labour pressed Grant Shapps to "immediately insist" that hard shoulders are restored to smart motorways after a report from MPs raised further issues.
But Mr Shapps cautioned such action could put more drivers and passengers at risk of death and serious injury.
He added he has an 18-point plan, backed with cash, to get smart motorways "sorted out".
Concerns have been raised following fatal incidents involving broken-down vehicles being hit from behind.
A report by the Commons Transport Select Committee (TSC) said there is not enough safety and economic data to justify continuing with smart motorways.
It described the Government's decision in March 2020 that all future smart motorways would have all-lane-running - where the hard shoulder is used as a permanent live traffic lane - as "premature".
Controlled smart motorways - which have a permanent hard shoulder and use technology to regulate the speed and flow of traffic - have the "lowest casualty rates" of all motorways and major A roads in England, the report said.
Speaking in the House of Commons, shadow transport secretary Jim McMahon said: "It's been 10 months since I asked the Secretary of State to reinstate the hard shoulder immediately.
"No action followed and instead he ploughed ahead with smart motorway rollout.
"Since then whistleblowers have come forward confirming our worst fears: broken equipment, a lack of monitoring and ultimately lives being placed at risk.
"This failure has had a devastating impact on people's lives.
"Now the Transport Select Committee has published its damning report and the families of those who lost loved ones on smart motorways were forced into Parliament Square this week to protest.
"Will he do the right thing and immediately insist that the hard shoulder is reinstated today?"
Mr Shapps replied: "We all share the passion and desire to make sure our roads are as safe as they can possibly be.
"Sadly 1,700 people die a year on our roads. It is important we do everything possible.
"The Transport Select Committee, who he quotes, did not in fact say quite what he said.
"They actually say the evidence suggests that doing so - in other words, simply putting the hard shoulder back in - could put more drivers and passengers at risk of death and serious injury.
"It was Lord Prescott who started to introduce smart motorways. As far as I'm aware, I'm the first Secretary of State - and there have been 12 since - who has actually been working consistently with an 18-point plan and £500 million to get them sorted out."
