Starmer's infrastructure promise could take until the 2040s to deliver - will it be fast enough for voters?

Reset, revamp, or repetition? Call the prime minister's "Plan for Change" what you like, but it clearly puts planning front and centre.

The core pledge was one we first heard 14 months ago: 1.5 million homes built in England during this parliament.

The government admits it's a tough ask. It's not been met since 1972, when Keir Starmer was aged just 10.

But will it ease demand for housing? The Office for National Statistics projects England's population will grow some 2.1 million by 2029, largely through immigration. Those people will need houses.

So we crunched the numbers. Even if Labour meets their target, there would only be an extra nine houses per 1,000 people.

It would leave 2029's housing pressures nearly identical to today's.

Yet the prime minister's biggest challenge could lurk in his surprise commitment on infrastructure.

He promised to "fast-track planning decisions on at least 150 major economic infrastructure projects".

Re-read that carefully. The promise is not to deliver or approve 150 projects, but simply decide them.

And after all, "no" is still a decision. "150 decisions" does not guarantee 150 projects are coming soon to an area near you.

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Approval could end up being the easy part.

The National Infrastructure Commission chair Sir John Armitt says signing off and delivering 150 would be a "huge undertaking". That may be an understatement.

At the last count in March 2023, the government worked on 76 major infrastructure projects: everything from Sizewell C and HS2, to a polar research vessel, the refurbishment of the UK's Washington embassy and the Holocaust Memorial Centre.

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Sir Keir's commitment could mean tripling that.

The first issue is cost. The existing portfolio of 76 has a combined lifetime cost of... £403bn. That's over £5bn per project.

We have no idea how much an extra 150 would cost, not least where public or private cash would be found.

Second is capacity. Could the public and private sectors physically cope with triple the burden? And what productivity reforms would be needed?

And third: time. Our analysis of ongoing major infrastructure projects found they are expected to take, on average, 11.5 years to complete. Notre-Dame was rebuilt in half that time.

With this parliament running until 2029, it could feasibly be the 2040s before the commitment bears fruit.

As Labour sinks further in the polls, voters appear hungry for the promised "change".

The 2040s, if that's how long it takes, may be too long to wait.

Sky News' Trevor Philips will be speaking to Jamal Khashoggi's widow, Hanan Elatr Khashoggi, to get her reaction to Keir Starmer's visit to Saudi Arabia. He will also be joined by Deputy Prime Minister Angela Rayner and Lithuanian foreign minister Gabrielius Landsbergis. Watch Trevor Philips on Sunday at 8.30am this morning on Sky News, on Youtube and on the website and app.