Update: for anyone doubting the truth of this article, please note that today is 1 April.

This story was curated in conjunction with artists The Connor Brothers, who have also written for The Independent about what makes a good scam here.

Scotland and Wales are in preliminary talks to split away from the UK and form a new country if Britain votes to leave the EU in June.

The extraordinary proposal has been discussed by members of the Welsh Assembly and Scottish Government, and it is being taken seriously by the UK Government.

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The Independent can reveal the plans today after it was passed redacted documents by a Cabinet Office whistle-blower.

Under discussion are designs for a bridge or tunnel linking the two countries directly via the Isle of Man, with the “Celtic Union” among a number of name suggestions that would ultimately be decided at a second referendum.

Dubbed a “joint cessation”, the plans come amid concerns among Welsh and Scottish leaders that they will be pulled out of the EU against the wishes of their people.

Cabinet Office documents leaked to the Independent reveal discussions over a possible 'joint cessation'

Downing Street has tasked civil servants with compiling a list of the most dramatic possible outcomes in the event of a British exit.

Documents leaked from the resulting Cabinet Office committee meeting on “Brexit consequences” suggest David Cameron’s senior advisors are aware of the ongoing behind-the-scenes talks.

The files include redacted minutes from meetings where the idea of the “new nation” was discussed, as well as a map drawn up by civil servants to show how a proposed direct link between Scotland and Wales would work. They suggest the project would cost around £7 billion, and could be funded at least in part by the EU.

The files handed to the Independent include redacted minutes, emails and other materials

The Government is understood to be particularly concerned at the prospect of people passing into the new union being required to use passports.

And the committee also heard from a Bank of England expert who suggested splitting the country in two would result in “a prolonged period of stagnation” for both economies.

What has the EU ever done for us? Show all 7 1 /7 What has the EU ever done for us? What has the EU ever done for us? 1. It gives you freedom to live, work and retire anywhere in Europe As a member of the EU, UK citizens benefit from freedom of movement across the continent. Considered one of the so-called four pillars of the European Union, this freedom allows all EU citizens to live, work and travel in other member states. What has the EU ever done for us? 2. It sustains millions of jobs A report by the Centre for Economics and Business Research, released in October 2015, suggested 3.1 million British jobs were linked to the UK’s exports to the EU. What has the EU ever done for us? 3. Your holiday is much easier - and safer Freedom to travel is one of the most exercised benefits of EU membership, with Britons having made 31 million visits to the EU in 2014 alone. But a lot of the benefits of being an EU citizen are either taken for granted or go unnoticed. What has the EU ever done for us? 4. It means you're less likely to get ripped off Consumer protection is a key benefit of the EU’s single market, and ensures members of the British public receive equal consumer rights when shopping anywhere in Europe. What has the EU ever done for us? 5. It offers greater protection from terrorists, paedophiles, people traffickers and cyber-crime Another example of a lesser-known advantage of EU membership is the benefit of cross-country coordination and cooperation in the fight against crime. What has the EU ever done for us? 6. Our businesses depend on it According to 71% of all members of the Confederation of British Influence (CBI), and 67 per cent of small and medium-sized enterprises (SMEs), the EU has had an overall positive impact on their business. What has the EU ever done for us? 7. We have greater influence Robin Niblett, Director of think-tank Chatham House, stated in a report published last year: “For a mid-sized country like the UK, which will never again be economically dominant either globally or regionally, and whose diplomatic and military resources are declining in relative terms, being a major player in a strong regional institution can offer a critical lever for international influence.

The Independent attempted to acquire details of the proposal through a Freedom of Information request, but this was turned down by Cabinet Office officials.

Civil servants also saw a map with a proposed route for a tunnel or bridge connecting Wales and Scotland

Following the refusal, a set of documents was physically removed from Whitehall offices by the whistle-blower.

The Independent has agreed to protect his identity since the decision to remove official papers may have serious consequences for him. He has fled the country with the aid of transparency campaigners, and is currently safe in an undisclosed location in Moscow.

The fact that the full extent of consequences for Brexit has been kept under wraps by the Government will raise serious questions for Number 10.

The names of those present at the meeting, except senior civil servant Josephine Streicher, have been lost

Despite redactions it seems clear the committee, which has met at least three times in the past month, was preparing to brief ministers about secretive discussions between Welsh Assembly members and MSPs.

The Scottish National Party has already indicated that a vote to leave the EU would reignite the independence question, assuming that a majority of Scotland’s population votes to remain inside the EU. It is now apparent that Welsh Assembly members are considering similar moves.

In a final meeting, more drastic measures like a wall at the border are discussed

One member is minuted as querying whether cessation by Scotland and Wales would require a name change for the UK, left as an English and Northern Irish rump, including the idea of dropping the “Great” from Great Britain. It is unclear whether Northern Ireland’s Assembly at Stormont has been party to the Scottish and Welsh negotiations.