Ask Katie Lam which tax she dislikes most and the answer comes quickly. “My most hated single tax is stamp duty,” she said.

For good measure, she adds: “I dislike basically all tax.”

It is a neat summary of a politician who could hardly be further removed from the woman she shadows on housing and communities.

Lam has faced Angela Rayner across the despatch box twice since being promoted to the shadow cabinet last month, and she does not expect them to find much common ground.

“I think we will struggle to agree on very much at all,” she said. “But that’s politics, right? It’s the business of ideas.”

They arrive at those ideas from very different places.

Rayner, 46, grew up on a council estate in Stockport and worked as a carer before rising through the trade unions.

Lam, 35, was president of the Cambridge Union and spent most of her career at Goldman Sachs before entering Parliament in 2024.

That difference in outlook is particularly stark when it comes to their attitudes towards immigration.

Rayner recently reignited internal divisions within the Labour Party when she criticised Shabana Mahmood’s plan to make it harder for foreign workers to claim permanent residence in the UK.

Rayner has argued the changes would hit foreign care workers who had “moved their lives to look after our loved ones”.

The Home Secretary’s plans would extend the wait for permanent residence migrants from five years to 15, applied retrospectively to those who arrived from 2021.

More than 100 Labour MPs and the unions oppose them.

Mahmood has since signalled she could water the plans down and is due to meet union leaders to discuss the proposals this week.

However, Lam claims the Conservatives would go further than Mahmood and regard the proposed changes as “the absolute minimum” needed to restore the public finances.

In an interview with The i Paper on the opening day of the Conservative Party conference in Birmingham, Lam offered Tory votes to help Mahmood force through her immigration reforms in the face of a Labour revolt.

“If Angela Rayner and any of her other colleagues oppose them, then our Conservative votes are available to help her get them through Parliament,” she said.

She also turned her fire on the unions, which have been campaigning to exempt existing and new care workers from the rules. “It is amazing to me that unions whose job is to champion workers are advocating for a system whereby the only way that we can fill these positions is to systematically underpay people,” she said, calling their stance “completely indefensible”.

On Rayner’s call for care workers to be carved out of the changes, Lam pointed to the health and care visa. She said the projection had been for 6,000 arrivals annually but that 600,000 people came over three years, on entry-level salaries of about £20,500.

“Those people are almost guaranteed never to be net fiscal contributors. We can’t do that again,” she said.

She acknowledged that funding pressures on councils, which pay for much of social care, were “very acute”, but said: “Encouraging people to come to this country in order to do roles for less than a market rate is bad for literally everybody involved.”

Lam also backed her party’s policy of prioritising British families for social housing. She said the duty of British politicians was “to look after people who are British”.

The policy, along with restricting welfare to British citizens, was fundamental to getting a grip on the Budget, she said, claiming that one in six people on universal credit was not a British national.

Lam took aim at another of Rayner’s long-standing political causes: devolving power from Westminster to mayors like Andy Burnham – giving them increasing control over billions of pounds of public money.

It comes as the Prime Minister faces questions over his relationship with Manchester City’s Abu Dhabi owners.

Burnham has been accused of being too close to Manchester City’s owners after he said he would be “really concerned” if they left the city and praised the billions they had invested there.

His comments came just days after a Premier League independent commission found the club guilty of 80 charges relating to financial wrongdoing and 34 of 35 charges relating to failing to co-operate.

Burnham has since faced calls to publish details of every meeting he held with City’s owners during his time as mayor of Greater Manchester, as well as any hospitality he received.

For Lam, the controversy highlights a much wider problem with the way Britain’s increasingly powerful metro mayors are held to account.

There was “no question that there needs to be more accountability” if mayors are to be handed greater powers and control over billions of pounds of public money, she said.

Lam believes mayors should be required to face MPs and select committees “in a more structured way, in a similar way to how departmental ministers have to answer questions”.

“I don’t know exactly what that system would look like, but if the powers are going to have to be given, there has to be a way to hold these people accountable,” she said.

In a wide-ranging interview, Lam insisted the Conservatives were “totally committed” to the pensions triple lock – just days after she was heard in a leaked recording suggesting it could not survive.

In the recording, revealed by on Friday, she told Tory activists in June, before joining the shadow cabinet, that “what we will need in the end is an entirely new pension system” and that the system as it stood “can’t stand for very much longer”.

Asked by The i Paper whether the party’s policy was sustainable, she replied: “Yes, yes, absolutely. We’re totally committed to the triple lock.”

Lam said that while the nation’s finances were “totally unsustainable”, it was “absolutely deplorable” that the Prime Minister was starting with people who “have paid tax and worked for decades and decades” and could no longer go out and get another job.

Savings should instead come from getting people back to work and paying welfare only to British citizens who really needed it, she said, though she accepted that an ageing population meant “there will need to be a fundamental solution for social care”.

Asked whether she shared Kemi Badenoch’s desire to cut inheritance tax, which the Tory leader described as “morally right” amid claims she will make an announcement in her conference speech on Wednesday, Lam said: “I dislike basically all tax.”

“My most hated single tax is stamp duty,” she added, backing her party’s pledge to abolish it on people’s main homes. She said the tax was “a massive disincentive to downsize” for older people in homes that had become very valuable, because moving would cost them “tens of thousands of pounds” that went to the Exchequer.

Abolishing it would reverberate through the market, she argued: downsizers would free up family homes, and families moving up would free up starter homes for young buyers, for whom owning a home was “far too distant a dream”.

“I am pretty negative on almost every tax,” she said. “So I absolutely share Kemi’s aspirations… to get all of them down.”