Banks are making it harder for homebuyers to get their desired loan as the cost of living crisis bites.

Mortgage brokers have warned customers should act quickly as many of the big banks are tightening their mortgage affordability tests,  putting an end to the era of rock bottom rates.

It is making it harder for consumers to borrow as much as previously and is expected to slow the property market, as buyers are forced to downgrade their ambitions.

Santander amended its criteria last week and brokers told the Guardian they expect the other big lenders - HSBC, Barclays, Lloyds Banking Group and NatWest - to follow suit.

Ray Boulger, a senior analyst at the broker John Charcol said this was "arguably the biggest tightening in mortgage lending since 2009".

Enzo Mora, founder and CEO of Mortgage Brain based in Gloucester, said: "The lenders made amendments to their affordability calculators last week to coincide with the new tax year and to reflect the ONS data demonstrating the true rising cost of living.

" They have applied the new National Insurance contributions, council tax increases and growing gas and electric bills. This has meant that many of our customers have been affected negatively in terms of their maximum borrowing capability.

"The value of advice is now more important than ever before. With mortgage interest rates unstable and rising rapidly we want to find the best solution for our customers and they need to act quickly to minimise the impact on their monthly budget."

Since the financial crisis more than a decade ago, mortgage applicants have had to undergo strict affordability checks to ensure they can keep up with repayments. Banks want to know all their significant outgoings, including monthly expenses on childcare, car repayments and even how much they spend on the gym.

But many banks rely on household spending figures from the ONS to judge a borrower's spending. This data will now take into account soaring energy bills, the national insurance rise and a big increase in the cost of household goods.