Boris Johnson has insisted Brexit holds no 'terrors' for Britain but admitted for the first time there could be 'minimal controls' on the Irish border.
The Foreign Secretary insisted Britain would do well if it was forced out of the EU without a deal, even while ministers try to negotiate a free trade deal.
The leading Brexiteer hit out after Brussels chief Donald Tusk repeated warnings Britain could not have a bespoke trade deal - or any deal before resolving the Irish border question.
Mr Johnson can expect to be condemned by Remain supporters for painting a rosy picture of a no deal scenario that official forecasts suggest would damage the economy.
Downing Street insisted today 'minimal controls' was not inconsistent with the Government's commitment there will be no hard border and no physical infrastructure.
Boris Johnson (pictured right on a visit to St Leonard's C of E Primary school in Hastings yesterday) said there was 'no need' for a return to a hard Irish border
The Foreign Secretary also insisted Britain would do well if it was forced out of the EU without a deal, even while ministers try to negotiate a free trade deal
Speaking to an audience of Telegraph subscribers Mr Johnson said Brexit would be 'triumphant success'.
The Telegraph reported Mr Johnson said: 'I've never been one of those who is apprehensive about the so-called no deal scenario.
'No deal is better than a bad deal.
'If we have to come out on WTO terms we will be prepared to do so.
'It doesn't hold terrors for me and we will do very well under those circumstances as well.'
Mr Johnson also indicated he would be prepared to accept the timetable for the Brexit transition period set out by Brussels, expiring at the end of 2020.
'That would suit me fine,' he said.
The Prime Minister has suggested a transition period should last for around two years - which would expire near the end of March 2021 - while Brexit Secretary David Davis has put a range of between 21 and 27 months on the deal.
Resolving how the Irish border (file image) will work after Brexit has become the most difficult issue in the negotiations with the EU
On the issue of the frontier between Northern Ireland and the Republic, Mr Johnson said it 'will be possible to have very, very minimal controls at the border'.
He said the issue 'has understandably a great deal of political, emotional charge' and it is 'all too forgivable for politicians to wish to be absolutely certain about how things will work'.
Best for Britain champion Tom Brake. 'The only thing that is minimal seems to be Boris' grip on reality.
'The government for months have said there will be no controls at the Irish border and now there could be some. They seem utterly clueless.'
Last summer, the Government said there should be no physical infrastructure, such as customs posts, at the border, which has almost 300 crossing points.
In a position paper, ministers said they did not envisage CCTV cameras or number-plate recognition technology around the border.
Mr Johnson said the issue 'has understandably a great deal of political, emotional charge' and it was 'all too forgivable for politicians to wish to be absolutely certain about how things will work'.
European Council president Donald Tusk yesterday warned that EU negotiations could grind to a halt if UK proposals to prevent a hard border are not put forward within weeks.
Standing alongside the Irish premier Leo Varadkar, EU Council President Donald Tusk yesterday demanded an 'explicit, specific' solution to the border
What are the options for the border between Northern Ireland and the Republic after Brexit?
Theresa May and Jean-Claude Juncker agreed the outline of a divorce deal in December
Theresa May and the EU effectively fudged the Irish border issue in the Brexit divorce deal before Christmas.
But the commitments to leave the EU customs union, keep a soft border, and avoid divisions within the UK were always going to need reconciling at some stage. Currently 110million journeys take place across the border every year.
All sides in the negotiations insist they want to avoid a hard border between Northern Ireland and the Republic, but their ideas for how the issues should be solved are very different.
If they fail to strike a deal it could mean a hard border on the island - which could potentially put the Good Friday Agreement at risk.
The agreement - struck in 1998 after years of tense negotiations and a series of failed ceasefires - brought to an end decades of the Troubles.
More than 3,500 people died in the 'low level war' that saw British Army checkpoints manning the border between Northern Ireland and Ireland.
Both London and Dublin fear reinstalling a hard border - whether by checkpoints or other means - would raise tensions and provoke a renewal of extremism or even violence if people and goods were not able to freely cross.
The DUP - which opposed the Good Friday Agreement - is determined to maintain Northern Ireland inside the UK at all costs, while also insisting it wants an open border.
The UK blueprint:
The PM has made clear her favoured outcome for Brexit is a deep free trade deal with the EU.
This would mean being aligned closely enough with the bloc that there is no need for customs checks.
Any remaining gaps in customs regulations as a would be covered with technological solutions.
That is likely to mean cameras and electronic records, which would arguably not constitute major physical infrastructure.
Boris Johnson has suggested that a slightly 'harder' border might be acceptable, as long as it was invisible and did not inhibit flow of people and goods.
However, Brussels has dismissed these ideas as 'Narnia' - insisting no-one has shown how they can work with the UK outside an EU customs union.
The EU blueprint:
The divorce deal set out a 'fallback' option under which the UK would maintain 'full alignment' with enough rules of the customs union and single market to prevent a hard border and protect the Good Friday Agreement.
The inclusion of this clause, at the demand of Ireland, almost wrecked the deal until Mrs May added a commitment that there would also be full alignment between Northern Ireland and the rest of the UK.
But the EU has now translated this option into a legal text - and hardened it further to make clear Northern Ireland would be fully within the EU customs union.
Mrs May says no Prime Minister could ever agree to such terms, as they would undermine the constitutional integrity of the UK.
A hard border:
Neither side wants a hard border between Northern Ireland and the Republic.
But they appear to be locked in a cyclical dispute, with each adamant the other's solutions are impossible to accept.
If there is no deal and the UK and EU reverts to basic World Trade Organisation (WTO) relationship, theoretically there would need to be physical border posts with customs checks on vehicles and goods.
That could prove catastrophic for the Good Friday Agreement, with fears terrorists would resurface and the cycle of violence escalate.
Many Brexiteers have suggested Britain could simply refuse to erect a hard border - and dare the EU to put up their own fences.