Speaking ahead of the high-stakes speech, Sir Keir said he would ditch earlier pledges to hold onto key policies inherited from Jeremy Corbyn if it was needed to make Labour electable.
His keynote conference speech in Brighton on Wednesday will draw a firm line under the Corbyn era, with a promise to voters that Labour will never again go into a general election without a serious plan for government.
He will also launch an assault on the smallness and triviality of Boris Johnson’s approach to government, whose incompetence he argues has been exposed by the current fuel shortages and cost of living crisis.
A senior shadow cabinet minister told The Independent that Labour’s high command believe that the optimism and confidence that attracted voters to Boris Johnson will seem increasingly brittle in the economically difficult years ahead of an election expected in 2023 or 2024.
“There’s an ever-growing chasm between the optimism and the delivery,” said the shadow minister.
“Boris has set himself up to fail with the ‘levelling up’ stuff. When people are told their lives are going to be levelled up, they don’t think it means a government grant to do up a couple of shops on the high street, they are expecting something transformative. It’s a very high bar to reach and a very short period of time to achieve it in.”
In comments that infuriated Labour’s left, Sir Keir made clear he does not regard himself as bound by the list of 10 pledges from last year’s leadership election, which committed him to maintain key elements of Corbyn’s platform, including common ownership for industries like energy, rail and mail.
Speaking to BBC News, Sir Keir said he stood by “the principles and values behind the pledges” but added: “The most important pledge I made was that I would turn it into a party that would be fit for government, capable of winning a general election. I’m not going to be deflected from that.”
Asked whether party unity or winning elections was more important to him, he replied: “Winning. Winning a general election.”
Despite the resignation of the final Corbynist member of his shadow cabinet, Andy McDonald, on the third day of the Brighton gathering, Sr Keir and his team believe they have used the conference to create a launching pad for significant advances at the next election.
Rulebook changes approved by delegates will protect MPs from deselection by radical activists and reassure voters that a hard-left takeover will no longer be possible.
The Labour leader wants to use his first in-person address to the annual conference - forced online by Covid in 2020 – to make a strong impression on voters of who he is and the principles that underpin his politics.
In what was billed as the most personal speech of his political life, he will set out how his background and his values inform the politician he has become.
Following criticism that his first 18 months as leader have been dominated by internal party battles, he will focus on his plans for Britain and his appeal to voters – with eye-catching policy announcements expected to counter accusations that he has failed to be clear about how Labour would govern.
“Keir’s speech will be noticeably different from what you’ve heard from Labour in recent years,” said one party source.
“It will be more optimistic, more focused on the future, more outward-looking.”
Sir Keir will say that shortcomings in Johnson’s government, which were masked during the Covid pandemic by ministers’ reliance on expert scientific and medical advice, are now coming to the fore in the current crisis.
Problems with the disruption of supply chains and soaring prices were driven not only by short-term failures of government decision making but also by long-term neglect during 11 years of Conservative-led governments, he will say.
“I see the government lost in the woods with two paths beckoning,” the Labour leader will say. “One path leads back where we came from. None of the lessons of Covid are heeded. The divisions and flaws that were brutally exposed by the pandemic all worsen.
“But there is another path down which we address the chronic problems revealed by Covid with the kindness and the togetherness that got us through. That path leads to a future in which a smart government enlists the brilliance of scientific invention to create an economy in which people are healthy and well-educated. A contribution society in which everyone has their role to play.”
Setting out his determination to regain public trust after the Corbyn years, he will add: “Too often in the history of this party our dream of the good society falls foul of the belief that we will not run a strong economy. But you don’t get one without the other. And under my leadership we are committed to both. I can promise you that under my leadership Labour will be back in business.
Speaking to The Independent, a shadow cabinet minister said that Sir Keir’s route to No 10 lay in stressing the contrasts between his personality and Mr Johnson’s, rather than simply attacking the prime minister’s flaws.
“If you look at history, it’s very rare for one prime minister to be followed by another with a similar character,” said the shadow minister. “Voters decide it’s time for a change.”
And they added: “Boris is a very difficult opponent to beat, and you don’t do it by telling everyone what a terrible personality he has.
“People have repeatedly shown at the ballot box that they like his personality, and you don’t win them over by just telling them they are wrong.
“But no politician stays popular forever. He’s been through a whole list of scandals which would have killed any other politician’s career and I think a tipping point will come when people look at him and decide they don’t like what they see.”
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