Philip Hammond denied trying to delay Brexit today as Tory MPs demanded an end to damaging Cabinet squabbling.
The Chancellor insisted there was no prospect of EU membership continuing beyond March 2019, saying his push for a transitional deal would not mean 'postponing' the UK's departure.
The comments came after Downing Street slapped down Mr Hammond by dismissing his suggestion of a three-year transition with Norway-style arrangements. No10 made clear that free movement would end when we leave the bloc.
At a press conference in Brazil overnight, Philip Hammond acknowledged there was still a 'debate' about the nature of a transitional deal
The Chancellor has been meeting counterpart Henrique Meirelles in Brazil during a trade mission to the country
Cabinet colleagues including Boris Johnson and Liam Fox are said to have been infuriated by the Chancellor's 'freelancing' on Brexit in interviews last week while Theresa May is abroad on holiday.
At a press conference in Brazil overnight, Mr Hammond acknowledged there was still a 'debate' about the nature of a transitional deal.
But asked about the Brexit timetable, he said: 'No, it won't be postponed or delayed.
'As Michel Barnier, the EU negotiator says ... the clock is ticking, we are already in a timescale that has to end on March 29 2019, which is when Britain will leave the European Union.
'There's a discussion going on about how we then move from full membership of the European Union to a future relationship with the European Union and that's a debate, a discussion that will go on through this negotiations.'
He added that the UK hopes talks on a post-Brexit EU trade deal will begin this autumn.
The EU's chief negotiator, Michel Barnier, has raised the prospect of a two month delay amid a furious row about the huge divorce bill demand from Brussels.
Mr Hammond said: 'Of course it is then possible for us as a sovereign nation to negotiate future relations with the European Union, and that's the process that we hope to begin this autumn - of discussion with our European Union partners about the future trading relationship with them.
'But that trading relationship will not be based on membership of the European Union, it will be based on treaty - just like a future trading relationship with Brazil will be based on treaty.'
Former Foreign Secretary Lord Hague has waded into the row to urge ministers to keep the UK in the single market and customs union during the 'implementation phase'.
In his Daily Telegraph column, he said: 'This is seen by longstanding advocates of leaving as a 'soft' position or a climbdown. But in reality it is a plan to rescue Brexit from an approaching disaster.'
Theresa May and husband Philip left their