Shadow Chancellor Rachel Reeves yesterday ruled out any version of a wealth tax on the richest in society if Labour win the next general election.
She said that extra money for public services would have to come from economic growth.
Ms Reeves confirmed Labour would not target expensive houses, increase Capital Gains Tax or put up the top rate of Income Tax.
"I don't see the way to prosperity as being through taxation," she said.
The shadow chancellor said in an interview that Labour would instead do "whatever it takes" to attract business investment into the UK.
The interview comes as Labour steps up efforts to demonstrate it can be trusted with the economy - and further distance itself from the policies of former leader Jeremy Corbyn - ahead of an election expected next year.
Time with businesses
Ms Reeves said her preparations for government include "spending an awful lot of time with businesses".
Labour says it has it has attracted a surge of interest from businesses at its key party conference, which takes place in October. The party said the number of attendees at its business forum has gone up by 50% in a year.
The BBC says the party's leadership has been insisting for some time that it will not make unfunded spending commitments.
But the left has said Labour should instead raise taxes, rather than lower its sights - and left-wing campaign group Momentum described the latest move as "shameful".
The group said in a post on X, formerly Twitter: "Wealth taxes are hugely popular. This is a Labour Leadership in hock to corporate interests."
Labour's strategists are content to provoke the ire of the left, partly as a way to emphasise how far the party has changed since the Corbyn era.
Next election
But they are also trying to insulate Labour from anticipated Conservative attacks at the next election.
By explicitly ruling out tax options, they believe this will blunt Tory warnings of a Labour tax bombshell to come.
The Conservatives, though, have accused Labour of taking people for fools, arguing that even the party's existing policies would push taxes up.