Prime Minister Boris Johnson has quietly embarked on a campaign to remove any reference to the European Union throughout tens of thousands of Britain’s laws, in what is being described in Whitehall as “Operation Bleach”.

In an attempt to cement the effect of Brexit into the laws of the land, civil servants have been ordered to scan through regulations and statutory instruments (SIs) spanning the four decades in which the UK was a member state of the EU.

The hope is that by removing any reference to the bloc, it would be more difficult for a future Labour Party government to dismantle Brexit, according to The Telegraph.

One source told the paper that officials are “looking at how we can cleanse our legislative framework of references to EU law, any kind of impact of EU law. It is going to be a mammoth task because there are thousands of pieces of legislation — statutory instruments, regulations; that sort of thing.”

Government ministers said that “Operation Bleach” will need to be completed before 2024 when the next general election is expected to happen and there is a possibility of pro-Brussels government taking power.

“This is the Government to do it — if a future Labour government won’t,” one minister said.

The chairman of the European Research Group, Mark Francois, said that following the 2016 EU referendum, Brexiteers made the “fundamental mistake” of easing up after they thought they had won the fight.

“In contrast, the ardent Remainers redoubled their efforts and, after much Parliamentary chicanery, very nearly overturned the result,” Mr Francois said.

“We must never repeat our gross error and always remain vigilant against any attempt to rejoin, especially from a Labour Party, led by a Remainer at heart,” he added.

The government is also concerned that were there any remaining references to the European Union in laws or regulations, then British judges may choose to differ to rulings made by the European Court of Justice.

“The fear that people have was not that we would have another referendum but there would be a slow creep, making references to court rulings,” a government minister said.

“People have wanted it so that if there were any change of view by future governments, at the very least it can’t go unnoticed,” the minister added.

On Sunday the leader of the Labour Party, Sir Keir Starmer, pronounced that the party would abandon his pledge to fight to restore the free movement of people within the European Union.

The Labour leader said that it will be important for his party to be honest with the public and let their voters know it would not be possible to renegotiate the treaty with the EU.

“Whether we like it or not, that is going to be the treaty that an incoming Labour government inherits and has to make work. And it is not being straight with the British public to say we can come into office in 2024 and operate some other treaty,” he said.

There has been a growing split within the party ranks in the parliament, however, with former Labour shadow minister Rosie Duffield claiming that the majority of Labour MPs “haven’t given up” and are “desperate to rejoin” the EU.

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