Sir Keir Starmer is planning to introduce legislation that would let the UK follow European Union Single Market rules without giving MPs a vote.
As part of the Prime Minister's reset with Brussels, the UK Government will seek to pass a new law which would allow Single Market rules to be adopted through secondary legislation.
That is likely to mean new rules being rubber stamped by MPs as Parliament can either approve or reject secondary legislation but cannot amend it.
But the Prime Minister defended the move to use the so-called Henry VIII powers as he turned the UK away from Donald Trump’s America and towards closer ties with the European Union.
Amid the turmoil sparked by the US president’s actions and rhetoric, Sir Keir told BBC radio: “We're in a world where there's massive conflict, great uncertainty, and I strongly believe the UK's best interests are in a stronger, closer relationship with Europe, whether that's defence and security, of course energy, and also our economy.”
The Prime Minister, who has clashed repeatedly with Trump including over the Iran war, Greenland and tariffs, explained further: “What we're doing with this piece of legislation is trying to make trade easier so there's less burdens for businesses.
“That, of course, translates into lower prices, particularly with the deal we've got with the EU.
“This is predominantly food and agricultural prices, which I think most people would say, whatever we can do to get those prices down is a step in the right direction.”
A decade after the 2016 referendum on Brexit, which has left the UK with a multi-billion blow to its economy, Sir Keir added: “We've got to look forward now, not backwards.
“Let's go forward and recognize that a stronger, closer relationship with Europe is in the UK's best interest, particularly in a world that is as volatile as it is.”
Shifting to closer EU ties may also be in Labour’s political interests given the strong challenge from Zack Polanski’s Green Party with a poll suggesting it could win 12 seats in London at the next general election, as well as possibly gaining hundreds of council seats in the capital at the May local polls.
But Tory leader Kemi Badenoch argued that accepting Single Market rules without having a say on them would leave the UK in the “worst” of both worlds.
The UK-EU reset legislation enabling the use of the so-called Henry VIII powers is expected to be part of the King's Speech package set out on May 13 and will be subject to the full parliamentary scrutiny process as usual.
But critics said the plan to allow the use of secondary legislation for dynamic alignment with Brussels, changing the UK's rules to mirror those set in Brussels to make trade easier, would sideline Westminster.
A Government spokesman said: “The Bill will go through Parliament in the normal way.
“Any new treaties or deals with the EU will also face parliamentary scrutiny, and Parliament will have a role in approving new EU laws required under those deals via secondary legislation.
“This will allow us to deliver a food and drink trade deal worth £5.1 billion a year, backing British jobs and slashing costly red tape for our farmers, producers and businesses.”
Chancellor Rachel Reeves has set out that areas where the UK diverts from the Brussels rules should be the "exception, not the norm".
The Government has repeatedly made clear the UK will not rejoin the Single Market or Customs Union.
However, Cabinet ministers including Deputy Prime Minister David Lammy, MP for Tottenham, and Health Secretary Wes Streeting, MP for Ilford North, as well as other London MPs, have pushed the case for the UK joining a customs union with the EU.
London Mayor Sir Sadiq Khan has put himself at the helm of Labour calls for Britain to rejoin the European Union.
The plans under the new “UK-EU reset Bill”, as it has been unofficially called within Whitehall, would give the Government the mechanism to adopt EU rules in areas where it has signed deals with Brussels.
A Whitehall source said: “We are clear Parliament will have a role for new deals and on new EU laws applying under those deals.”
There are circumstances where votes can be held on approving pieces of secondary legislation, but they do not have the same level of scrutiny as a new law.
But any blocking votes would be likely to cause issues with the EU and could spark retaliatory action by Brussels.
Britain and the EU are aiming to finalise negotiations on a youth mobility scheme in time for a joint summit this summer.
They also want to secure a common sanitary and phytosanitary area, which would apply to the movement of plants and food, and agree on a way to link their emissions trading systems by that time.
However, shadow business secretary Andrew Griffith said: “Parliament reduced to a spectator while Brussels sets the terms is exactly what the country rejected.
“Labour's dire management of the economy has driven Starmer scurrying to Brussels to distract from his own failings.
“Labour are still fighting the referendum because they fundamentally cannot accept the democratic decision the British people made.”
Reform UK's deputy leader Richard Tice said the plan was “outrageous” and promised his party would “reverse such a betrayal” if it won power.
