The government has promised to shield working people from tax rises when it lays out its Budget on 30 October, which is expected to raise taxes by around £25bn.

It has promised not to raise levies on VAT, employee’s national insurance contributions, income tax, as well as corporation tax.

However, Keir Starmer was asked who he classed as a working person last night in an interview with Sky News at the Commonwealth summit in Samoa.

His definition was somebody who “goes out and earns their living, usually paid in a sort of monthly cheque” but they did not have the ability to “write a cheque to get out of difficulties”.

He was pressed if this would include people who get all, or part, of their income from assets, such as landlords or shareholders.

Starmer replied: “Well, they wouldn’t come within my definition.”

The Prime Minister’s comments will spark fears among landlords that they will be among the groups targetted for tax hikes in Chancellor Rachel Reeves’ Budget on Wednesday.

Changes to thresholds and tax exemptions to capital gains and inheritance tax as well as stamp duty may add thousands of pounds to their annual tax charges.

The Intermediary Mortgage Lenders Association executive director Kate Davies says: “It very unfortunate that the Prime Minister doesn’t regard private landlords as ‘working people’.

“We know from our Imla research, published last December, that there is a wide range of private landlords – but the vast number, 80%, own just one or two rental properties.

“Many will manage those properties themselves – and many will do so conscientiously and effectively.

“Some will be retired – and others almost certainly have to work to supplement the relatively modest income after tax, our report estimated the average was about £9,000 per rental property.  It seems rather harsh to consider them to be non-working.”

Buy-to-let owners also face a £21.5bn bill to upgrade their properties to new green government standards, according to data from rental deposit firm Zero Deposit last month.

All private and social rented homes will have to meet an energy performance certificate rating of C by 2030, according to August proposals set out by the Department for Energy Security and Net Zero.

Tax rises set to hit landlords in the Budget could push the rental sector crisis “beyond repair”, according to a survey from Octane Capital last month.

Octane’s survey of landlords found that 66% of them have already reduced the size of their investment portfolio in the last year, with “reduced profitability due to previous legislative changes cited as the primary reason for these reductions”.

The proposed ban on ‘no-fault’ evictions in the government Renters’ Rights Bill introduced to parliament last month, was also cited as a reason to leave the sector, along with the “inevitable increase in age”, as many landlords who invested in the 1990s approach retirement.