article: It follows reports in a German paper of repeated clashes between Theresa May and Commission president Jean-Claude Juncker at a Downing Street dinner. EU sources claimed UK misunderstanding of the talks process, and ignorance about how Brussels works, could lead to no deal being agreed on the UK's exit. Home Secretary Amber Rudd said the reports were "tittle-tattle". She said the emergence of the reports was "not the right way" of negotiating, but the UK was committed to negotiating in "good faith". According to the Frankfurter Allgemeine, the prime minister and Mr Juncker reportedly clashed over Mrs May's desire to make Brexit "a success" and whether the issue of protecting the rights of expat UK and EU nationals could be agreed as early as June. The newspaper claimed Mr Juncker said: "I leave... 10 times more sceptical than I was before." In a speech later on Tuesday, Mrs May - who has dismissed the account as "Brussels gossip" - will cite the need to stand up to the other 27 EU countries "We have seen in recent days, it will not be easy," she will say. "The negotiations ahead will be tough. Across the table from us sit 27 European member states who are united in their determination to do a deal that works for them." The German newspaper's report of the dinner last Wednesday, which looks to have come via European Commission sources, said that after the PM said she wanted to "make Brexit a success", Mr Juncker's response was: "Brexit cannot be a success. The more I hear, the more sceptical I become." And when she said the UK owes no money to the EU, the president informed her that she was not leaving a "golf club". The article said that, after last week's dinner, Mr Juncker was shocked at Mrs May's suggestion that a deal on citizens' rights could be achieved so quickly. The German newspaper report also suggested Mr Juncker said there would be no trade deal between the UK and the rest of the EU if the UK failed to pay the "divorce" bill which it is expected to be asked for. Reports also claim that the morning after the dinner last Wednesday Mr Juncker told German chancellor Angela Merkel that Mrs May was "on a different galaxy". A senior Conservative source told the BBC that the party would "rise above" all the media coverage but rejected accounts of the dinner, saying: "We really, really do not recognise those reports." Ms Rudd said the UK would not be responding to the claims but the government had set out a clear plan and priorities for the talks and Mrs May was the best person to negotiate a Brexit deal that was in the UK's "national interest". "Once you start engaging in gossip, in tittle-tattle in this way, it (will) carry on and who knows where it will lead?" she told BBC Breakfast. "Nobody knows how much truth there is in gossip. But there are ways of conveying what is going on and this is not the right way.
summary: The UK will not enter into "a briefing war" with the European Commission over Brexit talks, Tory sources have said.