Sir Keir Starmer has said £28 billion is “desperately needed” for Labour’s mission to achieve clean power by 2030 amid confusion over the party’s commitment to the investment pledge.

The Labour leader insisted he had been “unwavering” in relation to the party’s green energy plans and denied it was “scaling back” policies as this year’s general election looms.

Sir Keir originally announced £28 billion a year would be invested in sustainable projects if it wins power but has since said the figure will instead be a target for the second half of a first parliament.

Asked about the pledge in an interview aired on Tuesday, Sir Keir told Times Radio: “We’re going to need investment, that’s where the £28 billion comes in. That investment that is desperately needed for that mission.”

Labour business event
Labour leader Sir Keir Starmer has defended the party’s economic plans (Stefan Rousseau/PA)

“You can only understand the investment argument by understanding that we want to have clean power by 2030… We need to borrow to invest to do that.

“That’s a principle I believe in and I’m absolutely happy to go out and defend. And of course, what we’ve said as we’ve got closer to the operationalisation of this, is it has to be ramped up, the money has to be ramped up, the £28 billion et cetera, and everything is subject to our fiscal rules.”

He said he had “been unwavering in relation to the mission – clean power by 2030”.

It comes after shadow chancellor Rachel Reeves last week promised “iron discipline” in sticking to Labour’s fiscal rules, which include getting debt falling as a percentage of GDP.

Ms Reeves repeatedly refused to set out whether she is standing by the £28 billion-a-year figure, casting further uncertainty on whether the spending pledge would be kept.

Last month, Labour sought to kill off a report the target had been abandoned by saying it was “committed” to ramping up the investment “subject to our fiscal rules”.

The party has pointed to the changed economic landscape, including the turmoil caused by former prime minister Liz Truss’s mini-budget in 2022, when accused of watering down its flagship green prosperity plan first announced in 2021.

Chief Secretary to the Treasury Laura Trott said: “After weeks of chaos Keir Starmer has said Labour are not ‘scaling back’ from their £28 billion spending spree. This same old Labour approach of unfunded spending means higher taxes.

“He cannot say how he would fund his £28 billion spending spree because he does not have a plan to pay for it and that means higher taxes for hardworking people and uncertainty for British business.”