Before today’s announcement of an additional £2.1 billion of Brexit funding, a total of £4.2 billion had already been allocated by the Government to prepare for the UK’s departure from the EU.

Spending began in autumn 2016, a few months after the referendum, when £400 million was earmarked for Brexit.

This was followed in the 2017 Budget by a further £3 billion to be spent during 2018/19 and 2019/20.

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£250 million was drawn from the UK’s reserves in 2017/18 for Brexit spending, and at the 2018 Budget another £500 million was made available.

The Treasury has published a breakdown of how this £4.2 billion has been allocated.

Four departments have taken just over two-thirds of the total:

– The Home Office has received the largest portion – £935 million, or 22% of the total

– The Department for Environment, Food & Rural Affairs received £788 million (19%)

– HM Revenue & Customs was allocated £677 million (16%)

– The Department for Business, Energy & Industrial Strategy took £410 million (10%)

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Smaller amounts went to the likes of the Department for Transport (£120 million, or 3%), the Department of Health and Social Care (£71 million, or 2%), and the Food Standards Agency (£31 million, or 1%).

The additional £2.1 billion brings to £6.3 billion the total the Government has made available for Brexit.

£1.1 billion will be allocated immediately and a further £1 billion will be made available if necessary.

Of the £1.1 billion allocated immediately, the biggest portion (£434 million, or 39%) has been assigned to ensure medicines and medical products remain available.

£344 million (31%) is earmarked for border and customs operations, £138 million (13%) for public information campaigns, and £108 million (10%) for supporting businesses.