The UK could be hit with a £186bn bill from the European Union in the event of a eurozone bail-out unless Britain leaves under a managed clean Brexit, leading City and business figures have warned.
In a letter to Conservative Party constituency chairmen and senior Tory officials, the Brexit Coalition calls on members to support a new prime minister who is "committed unequivocally" to backing a clean WTO-based Brexit which would end the UK's massive contingent liabilities to the EU.
Brexit Coalition is new grouping that represents 29 diverse pro-Brexit campaigning organisations, including the Alliance of British Entrepreneurs, Artists for Brexit and Farmers for Britain as well as Labour Leave and Green Leaves.
To avoid the scenario in which the UK would have to rescue EU banks despite not being a member of the eurozone, the UK needs to leave the EU and cut its contractual ties as soon as possible"
Brexit Coalition president and former Liffe boss Daniel Hodson said this was is an "increasingly likely scenario" given the current state the eurozone.
He added: "These liabilities have not been discussed deeply enough in the Brexit debate.
"To avoid the scenario in which the UK would have to rescue EU banks despite not being a member of the eurozone, the UK needs to leave the EU and cut its contractual ties as soon as possible."
The public should be worried about a no-deal Brexit, the former top civil servant at the Department for Exiting the European Union has said.
In his first interview since retiring three months ago, Philip Rycroft, the former permanent secretary at DExEU, said: "I think everybody should be worried about what happens in a no-deal situation. We would be taking a step into the unknown."
He told the BBC's Panorama programme that while Brexit planning in the civil service was in good shape, leaving with no deal, which is one of the options favoured by the Tory leadership contender, would be "fraught with difficulty".
Boris Johnson has pledged to get the UK "match fit for no deal" to ensure it can leave the EU on 31 October "come what may". The Conservative leadership frontrunner said there would be "no second chances" as he stressed that the Halloween deadline was real, "not fake", in a comment aimed at his rival Jeremy Hunt.
Johnson's commitment to stick to the deadline comes after he was warned that more than 30 Tories could rebel to block a no-deal Brexit if he tried to force it through parliament.