The figure represents a fourfold increase since 2010, when costs stood at £567m.

The Labour Party, which obtained the figures, attributed the jump from £1.4bn in 2020/21 to £2.1bn in 2021/22 to slower asylum decisions, the rising backlog and the home secretary's "last minute decision-making" over the use of hotels.

The Labour Party said the asylum system was "completely broken and British taxpayers are paying the price".

Shadow home secretary Yvette Cooper said: "After 13 years, the Tories have broken the asylum system and these figures prove it.

"Nothing the government is doing is working, and their legislation is making the situation worse, with more people stuck in the system than ever before.

"Labour has set out serious plans for a cross-border police unit, fast-tracking to clear the backlog and a proper deal with Europe on safe returns."

A Conservative spokesman responded: "Labour's approach to asylum was a disastrous open-door policy coupled with massive amnesties.

"Given the chance they'd do it all over again. Labour are against deporting foreign criminals. Labour are against deporting illegal migrants. Labour are against stopping the boats.

"Only the Conservatives have a plan to tackle illegal migration as we deliver on our five priorities: halving inflation, growing the economy, reducing debt, cutting waiting lists and stopping the boats."

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The data comes after the UN's refugee agency identified significant failings in the UK's asylum system, including the detention of torture victims and laws not being "complied with".

In a scathing report, the United Nations High Commissioner for Refugees noted "numerous risks to the welfare of asylum seekers" after its investigation between 2021 and 2022.

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However, the Home Office said "significant improvements" have been made since the audit took place.

Separate Home Office figures released on the same day also showed the backlog of asylum cases in the UK hit a new record high.

A total of 172,758 people waited for an initial decision on an asylum application at the end of March 2023 - up 57% compared with the same period last year.

Labour also claims that over the past year, only 1% of small boat asylum cases have had a decision made and that the productivity rate of Home Office workers had fallen from 14 decisions per month in 2011 and 18 in 2016, to just five per month in the last financial year.

On Thursday Mr Sunak will head to Moldova for the European Political Community summit where he will warn that a rise in illegal migration and Vladimir Putin's war in Ukraine have created "unprecedented threats" at Europe's borders.

Mr Sunak is hoping to build on migration agreements secured with France and Albania and will begin negotiations for a returns agreement with Moldova.

He will also announce a new partnership with Bulgaria to help it destroy the business model of organised criminal gangs who are facilitating illegal migration.