This is down to “their low employment rates and wages” and “high rates of economic inactivity”.

The Migration Advisory Committee pointed to research in the Netherlands, which suggested the “lifetime net fiscal impact” of each asylum seeker was minus £390,000, while a similar study in Australia estimated a figure of minus £198,000.

And the MAC revealed the staggering cost of reuniting migrant families in the UK.

Researchers said 51,000 spouses who arrived in 2022/23 will cost taxpayers an alarming £5.6billion. This means every partner moving to the UK costs, on average, £109,000.

The true bill is likely to be far higher, as more than 60,000 foreign partners were issued with visas in 2023 and 2024.

Addressing the cost of asylum seekers, Chairman of the committee Professor Brian Bell said: “I would be very surprised if Australia and the Netherlands were not good comparators for us in terms of general labour markets in terms of the types of people who are coming on asylum.

“I don’t want to put a figure on it, but I think those sort of headline numbers that come from those countries, it wouldn’t surprise me if a similar order of magnitude was true in the UK.”

The MAC report said: “We expect the lifetime net fiscal impact of those entering through asylum and refugee routes to be unambiguously negative.

“This is largely due to their low employment rates and wages, high rates of economic inactivity and their exemption from the “no recourse to public funds” rule.

“For example, analysis by Migration Observatory suggested that 56 per cent of those who reported initially arriving in the UK to claim asylum and were of working age were in employment, compared to 75 per cent of the UK-born population.

“When in employment, their median annual salary was £20,000 for men and £18,000 for women, compared to £31,000 and £22,000 respectively for the UK-born.”

It added: “Note that many of those who enter through the asylum route will also have incurred substantial additional costs from being housed in asylum accommodation.”

The MAC report, published on Thursday, revealed the huge costs of the visa system which allows British-based sponsors to bring their partners to Britain.

It said one year’s intake of 51,000 foreign-based spouses who came here in 2022-23 ‘will incur a net lifetime fiscal deficit of minus £5.6billion in present value terms – an average of minus £109,000 per applicant’.

They were the ‘partners of British citizens and settled residents’, it said.

The MAC warned costs spiral once foreign partners are given settlement rights – and access to the NHS and benefits.

It said: “After obtaining ILR, an applicant is no longer subject to the NRPF rule and is eligible to access benefits.

“For example, we estimate that the cohort will claim £109m in benefits between Year 5 and Year 7, with claimants receiving an average of £2,400 in benefits per annum over this period.

“This figure accounts for the tendency of married individuals to claim fewer benefits.

“In addition, ILR removes an applicant’s obligation to pay the IHS and visa extension fees. This decreases their fiscal contributions.

“As the cohort ages further, the annual fiscal contribution becomes negative. This is a result of both declining employment income, as the cohort ages into ill-health and retirement, and the rising level of public spending allocated to them (particularly health, social care and state pension).”

They estimated that in just the three years after being granted ILR, the cohort of migrants granted the right to join their partners would claim £109m at an average rate of £2,400 per person.

Home Secretary Shabana Mahmood has vowed to overhaul settlement rules, with Labour considering restricting benefits to British citizens.

Those living on benefits must wait 20 to 30 years to receive indefinite leave to remain, under Ms Mahmood’s plan.

foreign nationals who arrived in the so-called ‘Boris Wave’ face a 10 to 15-year wait for settlement rights amid fears over an influx of low-skilled workers, particularly on the abused health and social care visa in the early part of this decade.

The new rules will apply to around 2.6 million people who arrived after 2021 – but won’t impact those already with settled status.

Foreign nationals applying for indefinite leave to remain must have no criminal record, speak English to A-level standards and have no debt, under Labour’s new proposals.

Under Labour’s new proposals, migrants making national insurance contributions will receive settlement after 10 years.

But higher and additional rate taxpayers will be able to secure indefinite leave to remain before that.

Someone earning £125,000 a year could achieve ILR in three years, Home Office documents show.