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Theresa May has attempted to reassert her authority after Boris Johnson set out his own vision for Brexit.
Asked about the foreign secretary's newspaper article, which sparked accusations of "backseat driving", the PM told journalists: "This government is driven from the front."
"We are all going to the same destination," she added.
Mr Johnson said he was trying to "sketch out" the "incredibly exciting landscape of the destination ahead".
He said: "What I am trying to do is set out, in advance of the prime minister's speech in Florence on Friday, because I was involved in that Brexit campaign, people want to know where we are going.
"It is a good thing to have a bit of an opening drum roll about what this country can do."
Media captionMr Johnson says he wanted to "sketch out" the "incredibly exciting landscape of the destination ahead"Johnson and statistics chief at loggerheads Does Mr Johnson's £350m a week Brexit claim add up? Brexit official moves to Number 10 Is PM heading for 'Florentine fudge' in speech?
The PM's comments were made as she flew to Canada to discuss post-Brexit trade with her counterpart Justin Trudeau.
Mr Johnson's 4,000-word Daily Telegraph article came ahead of Mrs May's major speech on Brexit in Florence on Friday.
Media captionTheresa May is making a big Brexit speech in Florence. But why do it there?
As well as saying the UK would "take back control" of about £350m a week after Brexit - and that much of this could be spent on the NHS - he said he opposed paying the EU to secure temporary access to the single market during a transitional phase after the UK's departure.
Asked about the foreign secretary's intervention, the PM said all ministers had agreed to the principles she had set out in her Lancaster House speech on Brexit in January.
She said: "We are all agreed as a government about the importance of ensuring the right deal for Britain, the right withdrawal agreement but also the right deal on a special partnership between the EU and UK for the future.
"We are all optimistic about what we can be achieving for the UK for the future."
By BBC diplomatic correspondent James Landale
After the heat of a political row comes the attempt by both sides to cool the passion.
So it was today between Theresa May and Boris Johnson.
The prime minister delivered a modest slap on the foreign secretary's wrist: "Boris is Boris", "this government is driven from the front".
Mr Johnson allowed himself a modicum of self-abasement: "There is only one driver in this car... and it is Theresa."
And that infamous 4,000 word article arguing against a soft Brexit?
A mere "opening drum roll" ahead of Mrs May's big speech on Friday.
But the differences of substance remain.
Mr Johnson said the UK after Brexit should pay for its "legal obligations" to the EU but not "extortionate sums" for access to the single market.
And he said the transition period should "not be too long".
So for now Mr Johnson lives to fight another day, saying talk of resignation is "barking up the wrong tree".
The test will come on Friday when we find out what Mrs May thinks about the Brexit transition, how long it should last and how much it should cost.
The political world will compare and contrast Mr Johnson's article and the prime minister's words in Florence. And then we will be able to judge if the gap can be bridged.
Pressed on Mr Johnson's suggestion of more cash for the NHS, she said: "By definition we are currently paying money into the EU, and there will be a point in the future when we've left the EU [when] we won't be paying that money into the EU.
"Of course we will have to decide as a government how to spend that money. And at the time we will look to see where we think it is appropriate and best to spend that money."
The row over Mr Johnson's article - which was criticised by the chairman of the UK Statistics Authority over its use of the £350m figure - came as the top official in the Brexit department was moved to the Cabinet Office.
In what BBC political editor Laura Kuenssberg said was a sign of Theresa May taking more control of Brexit negotiations, Oliver Robbins will now work more directly for the PM.
He will continue to lead the team of officials working on the Brexit negotiations.