The international development select committee study also said that aid spending per refugee in the UK had nearly tripled in three years, rising from £6,700 in 2019 to £21,700 in 2021.

Committee members said they were facing resistance from the government on obtaining exact figures on current spending. However, reportedly more £1 billion of the aid budget was spent on refugees in the UK in 2021, about 10 percent of the total.

The committee described the trend as unsustainable and unprecedented, and stated that it was the government’s political decision to spend so much on refugees in the UK, despite the fact that international rules defining legitimate aid do not require it to do so, the Guardian reported.

Under government rules, the Home Office can take money from the Foreign Office’s overseas aid budget to cover costs of a refugee’s first year in the UK.

According to the report, per capita spending on refugees exceeds that of any other OECD Development Assistance Committee (DAC) country between 2018 to 2021, and is roughly three times that of the DAC average of £7,400.

The Home Office's supplementary estimate includes plans for more than £2.6 billion in official development assistance (ODA) between 2022 to 2023, almost £2 billion more than the main estimate.

The main reason is that between March 2020 and September 2022, the number of asylum seekers housed in “contingency accommodation,” mostly hotels, increased from fewer than 2,600 to more than 37,000, the Guardian reported.

Partly as a result, in 2021 UK bilateral aid spending in least developed countries (LDCs) was slashed by 50 percent.

Given the government’s failure to provide full figures, the committee instead referred to claims by the respected Center for Global Development, which estimates that the amount of aid spent on in-country refugees in 2022 could surpass £3 billion, an increase of more than 300 percent since 2020.

UK-based charity Save the Children told the Guardian that those costs could reach £4.5 billion in 2022-23, accounting for one-third of the total aid budget.

“There has been a determined effort to prevent us from seeing the full picture,” Sarah Champion, the chair of the committee, told the Guardian.

“The government has wilfully attempted to prevent us carrying out our scrutiny role.

“Our attempts to access straightforward information about how the government is spending the ODA budget in the UK hit a brick wall.”

A Foreign Office statement said: “The government has acted decisively and compassionately to support the people of Ukraine and Afghanistan to escape oppression and conflict and find refuge in the UK, and at the autumn statement we provided an additional £2.5 billion to help meet the increased costs of this support.

“We report all aid spending in line with the OECD’s rules, which allow funding to be spent on food and shelter for asylum seekers and refugees for their first year in the UK.

“The UK government spent more than £11 billion in aid in 2021 and remains one of the largest global aid donors with most of it still going towards supporting the poorest communities around the world, helping tackle deadly diseases and getting millions of girls into school.”