President Donald Trump cancelled his approval of a landmark bill aimed at lowering Americans’ housing costs just hours ahead of a planned signing ceremony at the US Capitol.

Both chambers of Congress had earlier approved the legislation in a rare bipartisan move, signalling how pressing the issue has become for American voters across the political divide.

Trump wrote on social media that he would not sign the bill until a separate law on stringent voter ID requirements is passed. But unless the president vetoes the housing bill – or Congress adjourns – it could become law after ten days.

The bill, known as the 21st Century ROAD to Housing Act, has two key aims: reducing housing costs and increasing housing supply.

Experts have described the bill as the most comprehensive action from Congress on housing policy in the 21st century. It includes more than 40 provisions that target many housing-related issues.

But hours before he was expected to formalise its provisions into law, Trump posted on social media, saying: “Today’s Housing News Conference and Signing is hereby cancelled until such time as we pass the desperately needed SAVE AMERICA ACT, which I consider to be a National Emergency.”

The change in plan was a surprise to many on Capitol Hill, including some lawmakers who showed up to the signing only to be told by reporters that Trump had cancelled it.

Some Republicans told reporters they thought Trump would eventually sign the bipartisan bill into law. Others expressed confusion about the sudden shift from the president.

“That was his call to make,” Senate Majority John Thune told CNN ahead of a planned lunch with Senate Republicans and the president.

“What I would say is that the bill is a bill that’s been worked on for a long time. It’s an affordability issue, and eventually I hope he’ll find his way to sign it.”

Meanwhile, Senator Elizabeth Warren, a Democrat who co-sponsored the legislation, told CNBC she did not have “any idea” why Trump cancelled the signing.

“This just doesn’t make any sense other than whatever it is he wants to do, it’s a complete indifference to the cost squeeze on American families,” she said.

On Capitol Hill on Wednesday for lunch with Senate Republicans – about an hour after he was originally scheduled to sign the bill – Trump ignored reporters’ questions about the legislation and instead spoke briefly about the voter ID law he has championed.

The Safeguard American Voter Eligibility Act (SAVE) requires Americans to provide ID and proof of citizenship to vote. Trump has championed the measure, but Republicans, who control the House and the Senate, have said there is not enough support to get the measure over the finish line.

Housing has become a major issue in the US, with 89% of voters from across the political spectrum wanting action from Congress to make housing more affordable, according to a survey taken by the Bipartisan Policy Center this spring.

“Legislators and their staff really did their homework here to try to put together a package that was going to try to address a lot of concerns at once,” said David Gonzalez Rice, of the National Low Income Housing Coalition (NLIHC).

Among the provisions in the bill are efforts to make it easier to build homes and limits on how many single-family homes institutional investors can buy nationwide.

With a shortfall of more than four million housing units last year, according to an estimate from Realtor.com, the legislation targets the supply issue directly.

“Everyone can understand the idea that the more supply you build, the more it’s going to exert downward pressure on prices in your community,” Jared Grigas, Legislative Director at the National Association of Counties (NACO), said.

It also works to empower local governments to improve housing supply, “more than trying to micromanage them,” Grigas noted, getting rid of red tape and easing bureaucratic processes.

Both parties are taking the legislation’s success as their own with November’s midterm elections quickly approaching.

“It’s an achievement in terms of bipartisan policymaking in Washington, which is itself a recognition of how important this issue of housing affordability has become for the American public,” said Francis Torres, the housing and infrastructure director at the Bipartisan Policy Center.

He says there is a widespread recognition that there is an underlying housing supply problem that is driving America’s housing affordability challenges.

The median home price in the US is roughly $403,000 (£306,350), up from about $223,000 in 2010, according to data from the Federal Reserve Bank of St Louis.

A US family needs an income of about $117,000 a year to afford an average home on the market, according to the real estate broker Redfin, but that is nearly $30,000 more than what most US households earn, according to Census data.

Potential homebuyers also face high inflation and high interest rates, which have made homeownership even more out of reach for many Americans.

Republicans in Congress, especially those facing an uphill battle in their November races, have touted the bill’s incentives to speed up home-building as they vie to maintain control of both chambers of Congress and need legislative successes to do so.

They have emphasized that the legislation will lower costs and help Americans achieve “the dream of homeownership”.

Several smaller provisions in the housing bill will also have an impact on often-forgotten communities, experts say.

One measure makes it easier for communities impacted by natural disasters to get money on the ground to rebuild quickly, while another ensures that affordable housing remains available in rural areas of the US.

“It’s an accumulation of ideas, each of which moves the needle a little bit, but together they make up something meaningful,” Torres said.

“This bill is not going to be the thing that will change your rent cost in the summer of 2026 necessarily, but it is a crucial first step at the federal level to facilitate some important actions to add housing supply.” (BBC)

•Senate Majority Leader John Thune (L) and US President Donald Trump (R) speak to reporters at the Capitol.

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