Boris Johnson has strong views on Brexit "but so do I", Theresa May insisted as she attempted to downplay the Foreign Secretary's outburst on how negotiations are progressing.
The Prime Minister claimed "nobody ever said it was going to be easy" to quit the European Union but pledged to "deliver Brexit for the British people".
Mr Johnson's indiscreet remarks about Brexit, which saw him call for "guts" in the negotiations, emerged as Mrs May was on a flight to Canada for the G7 summit.
Quizzed by broadcasters on her arrival in La Malbaie, she said: "Boris has strong views on Brexit but so do I."
The Foreign Secretary told a private dinner there was a risk Brexit "will not be the one we want" and would keep the UK locked in orbit around the EU.
At the gathering of the Conservative Way Forward, a Thatcherite campaign group, he branded the Treasury the heart of Remain and claimed negotiations were approaching a moment of truth.
Mr Johnson was heard warning of a Brexit meltdown and said the UK could end up in the customs union and to a large extent still in the single market in the recording obtained by BuzzFeed News.
The Prime Minister was "going to go into a phase where we are much more combative with Brussels", the Cabinet minister said.
He also claimed fears about the border on the island of Ireland were out of proportion and said it was "beyond belief that we're allowing the tail to wag the dog in this way".
Mrs May told Channel 4 News: "These are complex negotiations. Boris has strong views on Brexit but so do I.
"I want to deliver for the British people, that's exactly what we are doing as a Government and if you look at the process of these negotiations - nobody ever said it was going to be easy."
It comes as the PM's latest Brexit proposals received a frosty reception in Brussels, Michel Barnier raising objections to her plan for a time-limited customs backstop covering the whole UK.
But within minutes of concluding a press conference in Brussels, the chief EU negotiator took to Twitter to correct the impression that he was rejecting the UK proposals out of hand, stressing that they would be the subject of discussions in the coming days and weeks.
Responding, Mrs May told the BBC: "This is a negotiation, Michel Barnier has said exactly that point.
"We have put a proposal on the table, on this backstop relating to Northern Ireland, we will now sit down and negotiate it with the European Union.
"We are getting on with the job and that's what the British people want."
Friends of Mr Johnson said it was disappointing that the private dinner had been covertly recorded but senior Conservative Sarah Wollaston said dressing up the comments "under the cover of a 'private' discussions won't wash".
Scottish First Minister Nicola Sturgeon said the Foreign Secretary had no credibility whatsoever.
Asked about the Foreign Secretary's remarks following a speech in Berlin, the Chancellor said: "My experience has been that a collaborative approach is generally more productive than a confrontational approach."