Sir Keir Starmer will say that Britons could be poorer than those in Poland, Hungary and Romania without a future Labour government’s growth plan.
The Labour leader will use a speech on Monday to set out how his economic vision is the “only show in town” to lead the UK out of the Conservative “low wage, high tax, doom-loop”.
If the country’s economy is not reignited, he will warn that Britain is at risk of a “brain drain”.
According to the party’s analysis of World Bank data, it predicts that wealth prospects in Britain are set to be surpassed within the next 20 years by eastern European rivals.
The speech in central London is set to expand on Sir Keir’s unveiling of five “missions” his party will focus on if it wins the next general election.
As well as commitments on energy, the NHS, crime and childcare, Sir Keir pledged to secure the highest sustained growth in the G7, along with providing good jobs and productivity growth in every part of the country.
Sir Keir is expected to tell voters that they will be able to “judge me on whether you feel better-off after five years of a Labour government”.
The Opposition leader, according to a pre-briefed extract of his speech, is set to say: “We need to be frank about the path of decline the Tories have set our country on.
“The British people are falling behind while our European neighbours get richer, in the east as well as in countries like France and Germany.
“I’m not comfortable with that; not comfortable with a trajectory that will soon see Britain overtaken by Poland.
“Nor am I prepared to accept what the consequences of this failure would mean.”
He is set to add: “I don’t want a Britain where young people, in our great towns and cities, are left with no option but to get out.
“A brain drain, not just to London or Edinburgh, but to Lyon, Munich and Warsaw. That’s not the future our country deserves.”
Labour said its calculations of Britain’s wealth decline were based on assuming UK gross domestic product (GDP) — a measure of the economy’s health — per capita continues to grow at a similar rate of 0.5 per cent in real terms as it did between 2010 and 2021.
That compares with 3.6 per cent for Poland, 3 per cent for Hungary and 3.8 per cent for Romania in the same timeframe.
Should that trajectory be sustained, then it would mean the average Briton would be poorer than their Polish counterpart by 2030 and less well-off than those residing in Romania and Hungary by 2040.
Labour said the party’s leader will pledge to “find the courage to take on vested interests” as he strives to “unlock the potential of every region and every nation” if he becomes prime minister after the next election, which is expected by the end of January 2025.
Officials briefed that Sir Keir will lay out how higher growth will be passed straight to families under his proposals.
A paper detailing Labour’s plan for meeting and measuring its progress on its growth mission will be published ahead of the speech.
The nine-page document, seen by PA news agency, says that having the highest sustained growth in the G7 would mean income growing faster, people having more savings, jobs in new and growing industries, along with vibrant high streets.
Sir Keir will argue that, having set out a Labour green prosperity plan, its ambitions to make Brexit work better and also enhance the British Business Bank, his party already has a “credible, long-term plan which represents the determination of our party to create more wealth”.
After the speech, the leader and shadow chancellor Rachel Reeves will host a roundtable of business leaders.
Conservative Party chairman Greg Hands said Labour’s plan for government included £90 billion of “unfunded spending”.
Mr Hands said: “The last time Labour left office, there was no money left, debt was spiralling, and unemployment soared – something the British people will never forget.
“Everyone already knows what Labour would do to the economy — with £90 billion of unfunded spending, that would just lead to endless borrowing and higher debt.”
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