Shadow Chancellor Rachel Reeves has insisted her plans for a Labour government are “not on the same track” as the Conservatives – as she stressed she was “absolutely committed to fiscal discipline.”

Ms Reeves has said she is “confident” Labour would hit its pledge of spending £28 billion a year on green initiatives within a first term of forming a UK government.

The party has angered its most climate-conscious supporters by watering down the pledge to borrow the sum to invest to tackle the environmental crisis.

Read more: Analysis: Can Keir Starmer's clean energy rhetoric match with real action?

Ms Reeves argued that the financial situation had worsened since making the commitment following Liz Truss’s disastrous mini-budget.

A set-piece speech by Labour leader Sir Keir Starmer this week was interrupted by protesters accusing him of U-turning on the policy.

But Ms Reeves insisted she expects they would ramp up green spending to £28 billion by the end of a first Parliament if Labour wins the next general election.

She told the BBC’s Sunday With Laura Kuenssberg programme: “We’re confident we can get there.

“We’re committed to it but it’s subject to our fiscal rules.

“All of our plans will be built on a rock of economic and fiscal responsibility. Labour will not play fast and loose with the public finances.”

Read more: Ross Greer: No Bute House with Labour if it opposes independence vote

Ms Reeves outlined in 2021 her green posterity plan to promptly after a Labour general election win spend billions on investing more in projects such as wind power and carbon capture.

But she now argues her fiscal rules – that debt must be falling as a share of national income after five years – are “non-negotiable”.

The SNP have criticised Labour for the perceived watering down of the climate funding and claimed the party cannot be trusted to follow through on its commitments.

SNP Westminster leader Stephen Flynn told Sky’s Sunday with Sophy Ridge that Labour “when it comes to some of these big issues, they have been changing their mind on an almost daily basis”.

He added: “I think it’s only quite clear to voters in Scotland that there’s one party who offers change and one party who offers real hopes, and that’s the SNP.”

Read more: Scotland to be UK's 'beating heart' under Labour's clean energy plan

Ms Reeves attempted to paint the Labour Party as the “only choice” for home ownership after accusing the Tories of having “broken” the housing market.

But as she also tried to bill her side as the ones being financially responsible, she insisted an injection of public spending was not needed to build houses.

“This isn’t about spending taxpayers’ money: this is about unblocking the planning system,” she told Ms Kuenssberg.

Ms Reeves disputed a report in the Sunday Times that her tax and spending policies would follow the Conservatives’ until growth returns.

“They’re not on the same track,” she told the BBC. “But I am absolutely committed to fiscal discipline.”

Labour has been flying high in the polls as the Tories struggle after 13 years of rule that have seen their popularity pummelled by issues including Boris Johnson’s partygate scandal.

But Ms Reeves, a former chess champion, deployed an analogy from the chequered board to warn against complacency in thinking Labour will win the general election expected next year.

“We’re a rook ahead after about 30 moves but we’re playing an opponent that usually beats us. So this is not in the bag,” she said.