The Bank of England (BoE) has launched a project to assess the economic risks to Britain if the country votes to leave the European Union in the referendum promised by Prime Minister David Cameron.
The existence of the bank's project emerged as the prime minister insisted he was "confident" of securing reforms in Brussels and indicated he remains open to staging the in/out vote next year, NewsNow reported.
The work done at Threadneedle Street was supposed to remain confidential, but was accidentally revealed when details were sent to a journalist in an email blunder.
According to the email inadvertently sent to the Guardian, the press and most staff were supposed to be kept in the dark about the work, which has been codenamed Project Bookend.
The newspaper said the email indicates that a small group of senior staff are to examine the effect of "Brexit" - a British exit from the EU - under the authority of Sir Jon Cunliffe, who as deputy director for financial stability has responsibility for monitoring the risk of another market crash.
The email, from Sir Jon's private secretary to four senior executives, was written on 21 May and forwarded by mistake to a Guardian editor by the bank's head of press, Jeremy Harrison.
In a statement, the bank said: "Today, information related to planned confidential bank work on the potential implications of a renegotiation and national referendum on the UK's membership of the European Union made its way into the public domain, due to an internal email sent inadvertently to an external party.
"It should not come as a surprise that the Bank is undertaking such work about a stated government policy. There are a range of economic and financial issues that arise in the context of the renegotiation and national referendum. It is one of the bank's responsibilities to assess those that relate to its objectives."
