Sir Keir Starmer said the Labour conference is the party’s chance to “set out the alternative” to the Tory Government’s “casino economics”.
Arriving in Liverpool on Saturday ahead of the annual gathering, the Labour leader said Prime Minister Liz Truss and Chancellor Kwasi Kwarteng had shown their “true colours” with their raft of tax cuts that mainly benefit the wealthy.
Sir Keir’s supporters hope he will use the four-day conference, which kicks off on Sunday, to capitalise on the unpopularity of the new administration’s economic measures.
The Government’s controversial programme of lifting caps on bankers’ bonuses, cracking down on benefits and vast tax cuts has widened the ideological rift between the two main parties and handed Labour plenty of ammunition.
Addressing a crowd outside Liverpool’s Pullman Hotel, Sir Keir said: “After 12 long years of Tory failure, didn’t they just show their true colours yesterday?
“Their driving ideology – make the rich richer and do nothing for working people.
“Well, this conference is our chance to set out the alternative, to make our case for an economy that works for working people, growth for everyone everywhere, wherever they are, a fairer, greener future. Let’s do it.”
Earlier, the Labour leader tweeted: “Tory casino economics is gambling the mortgages and finances of every family in the country.
“Labour will secure growth for working people, that benefits all communities.”
He is expected to link Conservative decisions to falling living standards and articulate a convincing vision to improve them.
Labour’s call for a heavier windfall tax on the profits of energy and oil giants to fund freezing energy bills – which Ms Truss is paying for by borrowing – will be a key plank of the argument.
Deputy leader Angela Rayner criticised the Government’s “trickle-down” economics and said her party would focus on “growth for the longer term”.
She told BBC Breakfast: “We wouldn’t be making the choices around the tax cuts at the moment, we don’t think that’s the way forward.
“We would be asking the oil and gas companies to pay a little bit more when they’ve made billions of pounds of profit, instead of putting it all on the national debt. We don’t think that’s the right priority.
“We’ve seen trickle-down economics before. It doesn’t work. We don’t believe it’ll stimulate the economy. And, you know, I think it will make the next generation worse off.”
She indicated Labour would reverse the scrapping of the top 45p rate of income tax, arguing “those with the broadest shoulders should pay more”.
Sir Keir will seek to project himself as a future prime minister in his speech on Tuesday, with his confidence boosted by a comfortable lead in the polls.
However, there are concerns that the gap is not wider despite the turmoil of former prime minister Boris Johnson’s government and while voters are still unsure about the direction his successor Ms Truss is taking.
Hopes that Sir Keir can lead the party to victory at the next general election will still be higher than at last year’s conference, which was seen as a make-or-break moment for him.
Sharon Graham, general secretary of the Unite union, told the BBC the Labour leader should “be bolder” in his economic policy and not “stand still” in order to win power.
This year’s event – only Sir Keir’s second in-person conference since taking the job – is expected to feature less internal division due to an exodus of left-wing members from the party.
But sources of tension could be debates over electoral reform and Sir Keir’s ban on frontbenchers joining strikers on picket lines, which cost Sam Tarry his shadow transport minister role in July.
Some dissent is possible during a rendition of God Save The King at the start of the gathering. Former Labour leader Jeremy Corbyn described the decision to sing the national anthem for the first time in recent history as “very odd”.
After Sir Keir leads tributes to the late Queen, Ms Rayner will open the conference with a pledge to end the Tory “procurement racket” and instead reward businesses that create local jobs, skills and regeneration.
One in six public procurement contracts issued by the Government in the last five years was won by businesses with links to a tax haven, Ms Rayner noted.
She said: “Under the next Labour government there will be no hiding place for cronies and no corner for corruption. We’ll give the Tory sleaze merchants their marching orders, end handouts to tax havens and strike off failed providers.”
The TUC welcomed the plans, which include the mass insourcing of public contracts.
General secretary Frances O’Grady said: “These proposals are much needed. Outsourcing has been a colossal waste of taxpayers’ money and led to a race to the bottom on workers’ pay and conditions.”
Other announcements will include a new Hillsborough Law to help prevent future injustices where there is state involvement.
Labour has also pledged to recruit care workers by guaranteeing fair pay, workers’ rights and appropriate training under a National Care Service as it claimed “too many private equity firms are failing” in their duties to residents.
The party is also reviving its “tough on crime, tough on causes of crime” slogan as it announces plans to prevent child exploitation and establish specialist rape courts to fast-track cases and support victims.
The Conservatives’ conference will take place in Birmingham from October 2-5. The Liberal Democrats cancelled theirs as it fell within the period of mourning after the Queen’s death.