George Osborne has admitted the Treasury is making contingency plans in case the United Kingdom votes to leave the EU at the referendum in June.
On Monday, Downing Street said it was not doing any contingency planning for Brexit.
Appearing before the Commons Treasury committee on Wednesday afternoon, the chancellor said there would be "serious implications" if the UK voted to leave.
"The Bank of England and Treasury are doing quite a serious amount of contingency planning for the impact on financial stability in the immediate aftermath of a vote to leave," he said. "I don't think it's appropriate to go into too much detail of that."
Osborne told MPs the UK would be "significantly worse off" should it leave the EU.
With the vote now just over a month away, the big beasts of the 'Leave' and "Remain' side have launched their referendum battle-buses.
Brandishing a bunch of asparagus spears and Cornish pasty, Boris Johnson has launched the Brexit roadshow.
"They think they have got the big battalions because they have the taxpayers’ money," he said of the pro-EU campaign.
"We have got the passion, we have got the commitment. Let’s make June 24 independence day for Britain,” he roared, waving a pasty.
Today, Gordon Brow said he would be happy to take on Boris in a head-to-head live TV debate over the EU referendum.
The former Labour prime minister used a speech at the London School of Economics to make his first big intervention in the referendum campaign, arguing the “patriotic” case for Britain to remain a member.
Asked by The Huffington Post if he would like to debate the former London mayor, Brown said: “I am happy to take anyone on these days.”