Nigel Evans MP has told talkRADIO that the government should consider pedestrianising Parliament Square as a safety measure.
After a car crashed into barriers outside the House of Lords this morning, he said "filtering traffic" would protect people in the vicinity.
Counter-terror police are investigating the crash.
"When I first got elected 26 years ago, there was none of that protection there," Evans told talkRADIO's political editor Ross Kempsell.
"There weren’t even armed police. All of that has been stepped up as a response to incidents in the past, and I suspect this will reignite the debate on whether the whole of parliament square should be pedestrianised to ensure that anybody can’t weaponise a vehicle and disrupt and indeed destroy out democracy."
Evans is referring to the Westminster Bridge attack of 2017, in which Khalid Masood drove a van into pedestrians and into the perimeter wall of the Palace of Westminster, before stabbing an unarmed policeman.
Extra barriers were installed on Wesminster, Waterloo and Lambeth bridges following the attack.
'If this was an attempted terror attack, he didn't think things through'
Of this morning's incident, Evans said there would have been staff in parliament despite it being in recess.
"Thousands of people would be working in parliament, at 7.30 in the morning there’d be people working in the restaurant and the cleaning staff," he said.
"There’d be very few members of parliament doing a recess on the parliamentary estate at that time. If it was an attempted terrorist attack he really didn’t think things through."
"If this is a terrorist attack the government need to respond to it," he added. When asked what should be done, he responded: "I suspect the pedestrianisation and the filtering of any traffic accessing this area so the point of entry for any vehicles is where we’re standing now. This will protect everybody on the parliamentary estate."
Watch Evans speaking above.