Sir Keir Starmer fears the general election will descend into gutter politics, with Rishi Sunak prepared to “go low” as he fights to hold on to the keys to No 10.
The Labour leader told business chiefs at his party’s conference that he was prepared for an election to be held next May, although Mr Sunak is thought to be considering holding off until autumn 2024 for the contest.
But Sir Keir said he expected the campaign to “descend into a place which isn’t about big politics”.
Sir Keir told them: “I’m not going to predict the outcome of the general election, nor when it will be.
“Though obviously it will either be May or October, and our team is ready for May because I don’t think anybody would rule out May.”
He added: “In terms of how it will be run, I think it will unfortunately descend into a place which isn’t about big politics.
“I think it will go low, from the Government’s point of view.”
He said that the decision to delay or water down net zero measures such as the shift away from petrol and diesel cars showed that “instead of making decisions in the long-term interest of the UK, the Government is in danger of making decisions in the short-term interest of opening up divides for the purpose of an election”.
“When a government gets into that place, whatever political party it is, that’s a bad place for the country,” Sir Keir warned.
In her speech, Ms Reeves will set out reforms to planning processes to speed up the way infrastructure developments can happen.
A Labour government would be prepared to borrow to invest, she said, but only within her fiscal rules which she will stick to with “iron discipline”.
Speaking to broadcasters ahead of her address, Ms Reeves reiterated her commitment to fiscal responsibility.
“We will only borrow if it is consistent with those fiscal rules,” she said, adding that could be “if debt is coming down by the end of the Parliament”.
Pressed on whether she would allow borrowing to invest if she enters No 11, she said: “As all countries do and as this Government does today. We will take it up to the level that is needed to compete internationally.”
The Labour frontbencher said the £28 billion the party plans to eventually invest annually in a green energy transition is “not all additional money”.
Asked where the cash would come from, she said: “Obviously, the Government is already spending money on some of these projects – the battery factory that they announced a few weeks ago. So, this is not all additional money.
“It is the total spending we want to see to help us secure for Britain these jobs in the industries of the future.”
Earlier, the director of the Institute for Fiscal Studies said it would be “very hard” to improve public services without additional tax rises.
Asked if Labour could stick to their spending plans without substantial rises in taxes, Paul Johnson told BBC Radio 4’s Today programme: “I’m not convinced that either a Labour or a Conservative government could do that.”
He said Labour’s plans to improve public services and the welfare system would be “very hard indeed” without “some tax rises, at least in the short run until and unless growth really does change”.
Ms Reeves responded by saying Labour’s top priority is growing the economy, because “if we were growing now at the same rate that we did in the 13 years of Labour government, then we would have tens of billions of pounds more without raising a single tax to invest in our public services”.
In her speech to Labour’s annual gathering, Ms Reeves will outline plans to modernise the UK’s creaking infrastructure as part of efforts to boost growth.
Planning applications would be fast-tracked for battery factories, laboratories and 5G infrastructure under the proposals.
She will tell the conference: “Labour’s task is to restore hope to our politics. The hope that lets us face the future with confidence, with a new era of economic security, because there is no hope without security.”
Her speech comes after the Prime Minister cancelled the HS2 rail line north of Birmingham due to spiralling costs and repeated delays.
The shadow chancellor will claim Labour would form “a government siding with the builders, not the blockers”.
Ms Reeves will say decision times for major infrastructure projects have increased by 65% since 2012, now taking four years, and will promise a “once-in-a-generation” set of reforms to speed this up.