David Davis has said the British people will not be "bullied" by Brussels after the President of the European Council warned Theresa May not to become "emotional" over Breit talks.
The Brexit Secretary backed Prime Minister's blistering attack on the EU for trying to interfere in the election and "run us over" in Brexit talks.
Speaking on BBC One's Question Time, Mr Davis said there had been a "deliberately misleading briefing" to the press after a dinner at Downing Street last week.
He added that "the line was crossed" when further stories appeared suggesting Britain would be hit with an exit bill of 100 billion euro (£84.5 billion), nearly double the previous estimates.
He said: "Clearly what was happening was the commission was trying to bully the British people - and the British people will not be bullied, and the Government will not allow them to be bullied.
"So she made the point she made, and she was right to do so."
It came after Donald Tusk, the EU Council President, warned that Brexit negotiations risk becoming "impossible" as he called for "discretion, moderation and mutual respect".
His message also appeared aimed at Jean-Claude Juncker, the President of the European Commission, after a scathing account of a meeting he had with Mrs May was leaked to the German press.
Mr Tusk said: "These negotiations are difficult enough as they are. If we start arguing before they even begin, they will become impossible.
"The stakes are too high to let our emotions get out of hand. Because at stake are the daily lives and interests of millions of people on both sides of the Channel.
"We must keep in mind that in order to succeed we need today discretion, moderation, mutual respect and a maximum of goodwill."
Sir Michael Fallon said Brexit talks would be easier if European Commission officials "kept their views to themselves".
The Defence Secretary bemoaned "one-sided leaking" from commission officials.
Asked if it would be easier if Mr Tusk and others did not comment on what is going on, he told BBC Radio 4's Today: "Well, it'd certainly be easier if commission officials kept their views to themselves and not further complicate what is already going to be a tough negotiation.
"But what's clear from Theresa May's reaction is that she is prepared, whatever the commission officials are doing in Brussels, to stand up for Britain's vital national interest in these very complicated talks."