Gordon Brown has called on Parliament to order Boris Johnson to commission an independent report on the consequences of a no-deal Brexit before taking the UK out of the European Union.
The former Labour prime minister said MPs should seize control of the House of Commons agenda for a day to pass a law making Brexit conditional on the production of an impact report.
Mr Brown said a no-deal Brexit would amount to an act of “self-harm” by the UK, putting lives at risk, and insisted that Mr Johnson was wrong to claim that he can guarantee supplies of vital medicines if Britain crashes out of the EU without a withdrawal agreement on 31 October.
Referring to MPs, Mr Brown told BBC Radio 4’s Today programme: “I think what they should do is agree that they take over the business of the House of Commons for a day, as they did before, pass a law that says that the Government must instruct and produce an independent report on the consequences of a no-deal.
“And that should be before the House of Commons and debated by the House of Commons before we ever go ahead.
“That would be a sensible way forward. It’s a common-sense approach to say we have got to look very carefully at the consequences of no-deal.”
Mr Johnson has insisted Britain will quit the EU by 31 October with or without a deal with Brussels.
But Mr Brown said that MPs would have on their consciences any negative consequences of a crash-out Brexit on individuals’ lives.
Asked if he believed the PM could guarantee that vital medical supplies would continue uninterrupted in a no-deal scenario, Mr Brown said: “I don’t think he can. I have looked at the words of the commercial director of the NHS who says there is going to be a significant shortage in the first three months and a serious shortage in the first few weeks.
“Nobody can tell us now what the level of disruption could be.”
He added: “Whether you are for or against Brexit, I think it is absolutely clear that in the referendum nobody promoting Brexit said the inevitable outcome would be a no-deal.
“Half the medical supplies we use come through Europe. If we are denied epipens or other important medical devices because of a slowdown at ports, then we are putting lives at risk.
“Any MP has got to take into account that their constituents may have voted for Brexit or not for Brexit, but on your conscience is what is happening to individual lives as a result of a poor decision.”
Mr Brown said that Johnson cannot resolve the problem of Brexit by calling a snap election.
“My view is that an election will not at this point solve the problem we have, which is making sure we don’t inflict harm on ourselves – self-inflicted wounds, self-harm – by leaving the EU with no deal.
“That is the issue that’s got to be addressed, that’s got to be faced up to by MPs when they return.”