The Labour leader will host a round table in the city of London on Monday, with prominent business guests.

He will flesh out more details of his "mission" for the UK to achieve the fastest sustainable growth in the G7.

Tesco chairman John Allan, and former Bank of England governor Mark Carney are due to attend.

Sir Keir is drawing together previously announced policies as well as setting out further details of Labour's economic strategy - including promises to provide clear rules for government taxation and spending, and announcing a new enhanced role for the Office for Budget Responsibility (OBR).

Labour said the Tories had put the country on a "path of decline" and if recent growth trends continued, people in the UK would be worse off than Poland's population by 2030.

It said UK GDP per capita grew at an average annual rate of 0.5% in real terms between 2010 and 2021, while Poland's grew 3.6%, (based on World Bank data).

If those trends continued, by 2030 people in the UK would each be £500 ($600) poorer than Poland's population, Labour said, and by 2040 would have fallen behind Hungary and Romania.

Labour announced last week that if elected, it would pursue five "missions": the first is for the UK to achieve the "highest sustained growth" in the G7.

The other missions - broad themes on what Labour wants to achieve in power - include turning the UK into a "clean energy superpower", improving the NHS, reforming the justice system and raising education standards.

The party has promised to provide more specific policy proposals later in the year. But Monday's event is to flesh out its general strategy for boosting economic growth and to sound out business.

"We've got to find the courage to take on vested interests," Sir Keir is scheduled to say later.

"So, if you think it's not government's role to shape markets, that we're only here to serve them; or that a labour market which locks in low pay and productivity is something beyond reform; or that the planning system should favour the already wealthy, not the new houses, wind farms and laboratories we need to create more wealth… then that's not going to work for us," he will say.

In the first indication of how the mission on the economy would be measured, Labour said it would look at growth in output per person and compare that to other countries.

It also plans to look at living standards via the measure of disposable income for the median UK household, with the ambition to make progress towards eliminating the gap between the median British family and those in France and Germany by the end of the parliament.

However Sir Keir will also suggest he should be judged on whether people "feel better off" at the end of a Labour term in government.

Paul Drechsler, former president of the business organisation the CBI, said Labour's strategy reflected the views of many of the country's business leaders, and he welcomed its commitment to "greater certainty and stability".

Labour has been wooing the business community, suggesting it would provide long-term, stable government in contrast to last autumn's rapid change of Conservative prime ministers, and the disruption on the financial markets.

However, Sir Keir has previously said he supports the increase in corporation tax - from 19% to 25% - that is coming in April, arguing that businesses are more concerned about stability than taxes.

He has also previously promised sweeping constitutional reform, which he said would unleash potential in the nations and regions of the UK, and has said he would "make Brexit work".

Tesco's Mr Allan said: "Speaking personally, I believe many businesses will welcome Labour's commitment to achieving sustained economic growth.

"Growth can best be achieved by a partnership between government and business. Now we need to work together to create a detailed plan so that if Labour form the next government, they can hit the ground running on day one."

Lord Sainsbury, former chairman of the supermarket chain, has made a £2m donation to the Labour Party. He was a regular Labour donor when the party was last in power and served as science minister under Tony Blair but stopped donating in 2016.