Nigel Farage has insisted the deal Boris Johnson brought back from Brussels was “not Brexit”.

The Brexit Party leader said the divorce terms agreed by the Prime Minister would see Britain tied to European Union rules on fishing and standards to such a degree that trade deals with non-European countries – including the US – would be “hindered”.

He told a rally of up to 600 parliamentary candidates that his mission was to campaign for a “clean Brexit” and to remind voters of Labour’s “betrayal” in switching to support a second referendum.

Brexit Party chairman Richard Tice (centre left) with party leader Nigel Farage (centre) and Brexit Party’s Parliamentary Candidates (Aaron Chown/PA)

Outlining the party’s campaign objectives in the run up to the December 12 General Election, he said: “I want the country to know the sheer extent of Labour’s betrayal.

“I want the country to know that this new EU treaty is not Brexit and if it goes through, we will never get independence.”

Mr Farage, speaking in Westminster, said Mr Johnson had made Theresa May’s exit deal “slightly better” but that, in scrapping alignment on customs rules, he had managed to “hive off” Northern Ireland.

The MEP said the PM had, in the Withdrawal Agreement, conceded that a trade deal with Brussels would depend on staying part of the Commons Fisheries Policy and increasing the divorce bill from £39 billion to £65 billion.

“There will be no free trade deal unless our state aid rules stay in line with the European Union, meaning we couldn’t assist British Steel or anyone else we chose,” added the former Ukip leader.

“Any free trade deal would mean we would have to remain in regulatory alignment on social policy, employment policy, environment and even taxation.”

The 55-year-old said Mr Johnson’s deal would “hinder us” from striking free trade deals with “the rest of the world”.

He told the candidates: “Here is the problem with the proposition that Boris Johnson is putting to the British people – it is not Brexit.”

The Brexit Party instead favours a no-deal exit from the EU – which the party dubs a “clean break” – and for the Withdrawal Agreement to be abandoned.

Asked what the Conservative Party leader would have to do to secure Brexit Party support, Mr Farage told journalists: “He needs to get rid of the treaty. It is that simple.”

He described it as “absolute tosh” that the decision to stand candidates in almost every UK seat could cost the Tories a majority and possibly put Brexit at risk.

Referencing Ukip’s performance in 2015, he said: “We did far more damage to the Labour Party than we did the Conservative Party.

“Cameron would never have got a majority if we hadn’t taken four million votes in that election.”

The party would be targeting Labour voters in Wales, the north of England and the Midlands, he confirmed.

“The media and everyone else seems to have forgotten the fact that five million Labour voters voted for Brexit,” he added.

Explaining his reason for refusing to stand next month, Mr Farage, who failed to take South Thanet from the Tories in 2015, said he would be better served travelling the country supporting the party’s candidates rather than being “hunkered down” in a single constituency trying to become an MP.

Richard Tice, the businessman and party chairman, said former Tory leader Iain Duncan Smith was wrong to say Mr Johnson’s party was now the Brexit party.

“We know they are not the Brexit party – far from it,” said Mr Tice.

“We stand for a proper, clean Brexit. We stand for doing the job properly, not some dodgy con trick that we fear the Tories are trying to bring on the country.”