Steve Bannon says Boris Johnson has done a "terrific job."

The new prime minister will provide "true leadership," according to Donald Trump's former chief strategist.

Bannon — a controversial right-wing activist — told BBC Radio that Prime Minister Johnson should deliver a no-deal Brexit: "I've said from the beginning a no-deal, hard out, is the way to go."

He also described an alliance between Johnson and Nigel Farage's Brexit Party as "natural."

Anti-Brexit campaigners said a Bannon endorsement "should be the kiss of death for a politician."

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Boris Johnson has a done a "terrific job" and will provide "true leadership" as prime minister of the United Kingdom, according to Donald Trump's former chief strategist Steve Bannon.

Speaking to BBC Radio 4's Today programme, Bannon said "it was inevitable that someone like Boris would come to the forefront" after the UK failed to leave the European Union over three years after the referendum.

Bannon is a controversial right-wing campaigner — who, after a spell in the White House advising President Trump — last year launched a movement designed to spread populism in Europe and undermine the European Union.

He has close ties with Brexit Party leader Nigel Farage and has described far-right British activist Tommy Robinson, who is currently serving a nine-month prison sentence for contempt of court, as the "backbone" of the UK.

Last year, he said Johnson had "nothing to apologise for" and should not "bow at the altar of political correctness" after he triggered outrage by comparing Muslim women who wear burkas to letterboxes.

Bannon told BBC on Tuesday that he has had "not much" contact with Johnson since he became prime minister.

He said: "Boris has done a terrific job. He laid out a case — but you've got to deliver."

He encouraged the prime minister to deliver a no-deal Brexit, telling BBC Radio: "I've said from the beginning a no-deal, hard out, is the way to go. But is the civil service bureaucracy in London prepared to do that? I don't think so."

The former right-hand-man to Trump said British politics was entering a "red zone" because the UK still had not left the EU after voting to do so over three years ago in 2016.

"If you're not out, I think it really fundamentally changes British politics," he said.

"Brexit and the Trump election are inextricably linked. Here we are two-and-a-half or three years later, and you're still not out. Now you have a hard deadline of October 31.

"In the European Parliamentary elections you could see that, where the Brexit Party came out of nowhere.

"People have got to remember that Nigel Farage is the only individual in political history in England to win two national elections with entities he kind of created himself."

He said that an electoral alliance between Johnson's Conservatives and Farage's Brexit Party would be "quite a natural alliance" as the two parties share the same "core" beliefs.

"I think it would be quite a natural alliance. What the Brexit Party stands for — at least at the heart of it — is the core of what Conservatives believe in the United Kingdom," he said.

"Right now Boris seems to have his own plan, he has changed his Cabinet, so we'll have to see."

Labour Party chairman Ian Lavery said: "It's unsurprising that Trump's man in the US has praised Trump's man in the UK, as Boris Johnson prepares to sacrifice our NHS on the altar of a trade deal with America.

"You can tell a lot about a person from the kind of company they keep, and our Prime Minister seems pretty cosy with a white supremacist. Boris Johnson is a danger to our country."

Bannon's endoresement "should be the kiss of death for a politician"

Bannon in June revealed that he helped Johnson with a speech criticising ex-prime minister Theresa May in the run-up to his resignation from her Cabinet in protest against her Brexit deal with the EU.

Virendra Sharma, Labour MP and supporter of the Best For Britain anti-Brexit campaign, said: "Being endorsed by a racist like Steve Bannon should be the kiss of death for a politician."

He added: "Bannon wants a worldwide alliance of the far-right. Farage is in on it and would jump at the chance to team up with Johnson at an election to make sure he gets what he wants.

"We need to crash their party and spoil their unholy alliance by working together as internationalists. Stopping Brexit is the first step in that direction."