The favourite to be the next prime minister is will reportedly strip DExEU of all other tasks and tell civil servants there to focus all of their attention on preparing for a disorderly divorce.
Meanwhile, the former foreign secretary is facing growing pressure from Tory Eurosceptics to make Iain Duncan Smith, the former party leader, his deputy PM.
Members of the European Research Group of Tory Brexiteers believe the veteran Eurosceptic would act as a guard against Mr Johnson watering down his pledges.
Mr Johnson is widely expected to beat his Tory leadership rival Jeremy Hunt and take over from Theresa May in Downing Street next Wednesday.
He has promised to take Britain out of the EU by Halloween 'do or die' and with or without a deal.
However, critics in Westminster and Brussels are sceptical about whether Mr Johnson would actually pull the trigger on a chaotic split if the two sides are unable to strike a new accord.
Boris Johnson, pictured in central London this morning, will reportedly re-brand DExEU the Ministry of No Deal if and when he becomes PM next week
Tory Eurosceptics want Iain Duncan Smith to be Mr Johnson's deputy prime minister to guard against Brexit backtracking
The Times reported that the former mayor of London will overhaul DExEU immediately after taking office in order to show his doubters that No Deal is an option he is willing to pursue.
The re-shaped department would be tasked with overseeing a massive new public awareness campaign detailing what No Deal will actually mean for the UK.
Mr Johnson believes is vital to make sure business is ready for a disorderly divorce.
It is thought the Cabinet Office would take control of all talks with Brussels although the expectation is that discussions with the EU are likely to be less frequent than under Mrs May.
News of the Tory front runners DExEU plan came as it emerged that Mr Johnson is being urged to make his campaign chairman his deputy prime minister.
Mr Duncan Smith, who was credited with turning around Mr Johnson's bid for Number 10 after a number of early stumbles, is the choice of many Tory Eurosceptics for the senior role.
They believe that Mr Duncan Smith, a leading Eurosceptic with many years of frontbench experience, would act as a perfect defence against pressure from Tory Remainers and civil servants for the likely new PM to soften his divorce strategy.
One senior member of the ERG, which is chaired by Jacob Rees-Mogg, told The Sun: 'Boris will come under huge pressure immediately from the civil service to water down his campaign pledges.
'It is essential to have a wise head like Iain's alongside him to hold the line from day one.'
Mr Duncan Smith has been on the backbenches since he quit as work and pensions secretary in March 2016.
It also emerged today that Tory MPs on the 1922 Committee executive are looking at plans to change the current leadership rules to protect Mr Johnson against an early challenge from his opponents.
Sky News said this morning that the committee of Tory backbenchers could introduce a new rule which states that a new prime minister cannot face a vote of no confidence for one year.
Currently new leaders of the party have no such protection.