A tearful Andy Burnham delivered an extraordinary first Labour conference speech as prime minister, vowing to deliver a “new Britain” with plans to scrap the pensions triple lock, build a new social care service and overhaul the voting system.

In a rousing address, Mr Burnham pledged to end the “wrong direction” of the country since Margaret Thatcher’s reforms of the 1980s, which he said said had delivered deindustrialisation, deregulation, privatisation, austerity and Brexit, resulting in a “country run for vested interests, not in the public interest”.

He vowed to bring water, housing and energy into public ownership and confirmed his plans for a free national social care service on a par with the NHS, to be funded with changes to the triple lock guarantee on pensions – a policy likely to divide voters.

He announced he would take a fresh look at Brexit, hinting that rejoining the bloc could be on the agenda, as previously revealed by The Independent.

And he also signalled a plan for councils to force landlords and the owners of empty homes to sell their properties in a socialist policy, which even Labour governments of the past would not consider.

The prime minister grew visibly emotional as he shared his late father Roy’s own experiences in the care system, telling members in Liverpool: “The United Kingdom my dad represented is the one I believe in.”

But he admitted: “This country isn’t where any of us would want it to be.”

Under his plans to fund a new National Care Service, which would see Britons able to access care along the same principles as the NHS, the state pension would rise in line with inflation or 2.5 per cent from 2030 – whichever is higher – breaking the triple lock’s automatic link with increases in average earnings.

Mr Burnham said he accepted he “may pay a political price” for the move, but said “someone has to go through the pain barrier and rip the plaster off”.

He said: “This change will generate significant savings which we will use to build up our National Care Service.”

Officials expect the change to save £15bn a year by 2040. But the Institute for Fiscal Studies’ deputy director Jonathan Cribb said savings “are likely to be relatively small in the first few years, but rise substantially over time” and “we should not expect this reform to save enough that it could fund universal social care in the next parliament”.

Reform UK leader Nigel Farage immediately hit back at the plan, accusing Mr Burnham of “launching an offensive against our elderly”, while Tory leader Kemi Badenoch said Mr Burnham “wants to take Britain back to the 1970s – a time of more government control, more trade union control, and no economic growth”.

“Nothing Burnham announced today will do anything to fix Britain’s long-term problems. He had no plan to fix our stagnant economy. No plan to fund defence. No plan to sort out the spiralling welfare bill beyond more government schemes,” she said.

General secretary of the Unite union, Sharon Graham, said the prime minister was wrong for “pulling a lever” on the triple lock, adding: “Going to the well of pensioners before going for the super rich is wrong.”

However, economist Jim O’Neill, who advised the former Greater Manchester mayor on economic affairs as he prepared to enter Downing Street, praised the prime minister for the commitment, saying the decision shows “we have a prime minister who wants to lead”.

Cabinet ministers who had grown weary of the “tinkering” of Sir Keir Starmer told that they were delighted by “the clear direction and ambition” of their new prime minister “which has simply lifted the mood of the whole party”.

One senior minister said: “You may not agree with everything but at least we know what he wants to do and where he wants to lead us.”

The prime minister also took a strong stance on the damage inflicted on Britain since Brexit, admitting “Brexit has done more harm than good”.

Though Labour remains committed to its 2024 manifesto red lines on Europe, which promised no return to the EU’s single market, the customs union or freedom of movement, his speech marks a change in approach to Britain’s relationship to the bloc.

“Brexit hasn’t given us control. We’ve lost some of the control we had over our economy, as a decade of low growth has put us in a weaker position. And we’ve lost some of our control over immigration,” he said.

Mr Burnham said he would set out “options” on UK-EU relations later this year, telling members that Britain must decide on its “long-term relationship” with the bloc.

Another shocking announcement came as Mr Burnham announced a new national commission on electoral reform, and said Labour would include a manifesto pledge to change the first-past-the-post system used in Westminster contests.

“We will all have failed in our public duties if we carry on as we are and open the door of Number 10 to a divisive government on less than 30 per cent of the vote,” he warned.

He said Labour would go into the next election promising to change the system “so that everyone’s vote counts and everyone’s voice is heard”.

The announcement proved popular with delegates in the hall, but drew a lukewarm response from some Labour figures.

Skills minister Baroness Jacqui Smith said: “Electoral reform isn’t top of my list of priorities. Good luck to the commission. I shall be interested in what it comes out with.”

Mr Burnham also received yet another standing ovation as he unveiled new legislation to repeal “Margaret Thatcher’s ideological ban on public ownership of water companies”.

He said it would start a decade-long process to strengthen public control, with mayors getting “new powers to hold water companies to account, with tougher consequences for those which repeatedly fail”.