David Cameron has become the fifth former prime minister to criticise a new bill attempting to override the Brexit withdrawal agreement.
The Internal Market Bill will come before MPs later, with the government calling it an “insurance policy”.
Mr Cameron said he had “misgivings” over it and breaking a world treaty should be the “final resort”.
Former Tory PMs Theresa May and Sir Major , and Labour’s Blair and Gordon Brown have condemned the plan.
Earlier, Policing Minister Kit Malthouse called it a “practical” step.
He echoed comments made by Justice Secretary Robert Buckland on Sunday, who said the bill was there just just in case the united kingdom and EU don’t agree a post-Brexit trade deal.
Boris Johnson was expected to talk to reporters at an occasion later, but No 10 confirmed it had been cancelled thanks to urgent parliamentary business.
The government is predicted to win a choose the Commons afterward subsequent stage of the bill – which is predicted around 22:00 BST (21:00 GMT) – but it’s expected to face more difficulties in later stages, especially when the legislation heads for debate within the Lords.
But former Attorney General Geoffrey Cox has said he will vote against it, accusing Mr Johnson of doing “unconscionable” damage to Britain’s international reputation.
The PM’s special envoy for Freedom of faith or Belief, Tory MP Rehman Chishti, has resigned over the bill, saying: “I have always acted during a manner which respects the rule of law… [and] voting for this bill because it currently stands would be contrary to the values I hold dearest.”
Labour’s shadow business secretary, Ed Miliband, also called the proposed law “legislative hooliganism”.
The UK left the EU on 31 January, having negotiated and signed the withdrawal agreement with the bloc.
The two sides are now within the closing weeks of negotiations for a post-Brexit trade deal before the transition period ends on 31 December – with informal talks happening in Brussels in the week .
A key a part of the withdrawal agreement – which is now a world treaty – was the Northern Ireland Protocol, designed to stop a tough border returning to the island of eire .
The Internal Market Bill proposed by the govt would override that a part of that agreement when it came to goods and would allow the united kingdom to switch or re-interpret “state aid” rules on subsidies for firms in Northern Ireland , within the event of the 2 sides not agreeing a future trade deal.
Last week, Northern Ireland Secretary Brandon Lewis said the bill would “break international law” during a “specific and limited way”, resulting in swathes of criticism from all sides of the political spectrum.
Mr Cameron – who called the EU referendum when he was PM – said he had “misgivings about what’s being proposed”.
Speaking to reporters, he said: “Passing an act of Parliament then happening to interrupt a world treaty obligation is that the very, previous thing you ought to contemplate. It should be absolutely the final resort.”
Mr Cameron said the “bigger picture” was about trying to urge a trade affect the EU, urging the govt to “keep that context [and] that big prize in mind.”
The comments follow stronger criticism by the four other surviving former prime ministers of the united kingdom .
Mrs May, who still sits as an MP within the Commons, said breaking law of nations would damage “trust” within the UK, while Mr Brown said it might be like “self-harm” for the country.
Sir John and Mr Blair – who were both in office during key periods of the Northern Ireland social process – wrote a joint article within the Sunday Times accusing Mr Johnson of “embarrassing” the united kingdom and urging MPs to reject the “shameful” plan to override parts of the withdrawal agreement.
Mr Malthouse defended the bill, saying it “solves the matter that we’re faced with” over the longer term of trade with the EU.
He told BBC Breakfast: “What we’ve done is to mention transparently that this is often a situation which we expect may occur – certainly that’s what’s being intimated from the EU. it is a problem we’ve to unravel so here’s a bill that solves it.
“In the top those folks that oppose this bill need to tell us what the resolution is.”
On Sunday, Justice Secretary Mr Buckland told the BBC he hoped powers being sought by ministers would never be needed, which he would resign if the united kingdom ended up breaking law of nations “in how I find unacceptable”.
But Labour leader Sir Keir Starmer accused government ministers of handing out “misinformation” over the weekend and “spinning” the explanations they were pursuing the new bill.
He told LBC: “[Mr Johnson] is making an error reneging on a treaty – which will have reputational damage for the united kingdom .
Source: bbc news