The European Union's former Brexit chief negotiator Michel Barnier responded to comments former Number 10 adviser Dominic Cummings’ made about him during the Brexit negotiations. Mr Barnier dismissed the outburst as he said he was sure whether Mr Cummings "knew clearly what happened in the negotiations." The former Downing Street Chief of Staff called the EU diplomat "lazy, emotional bull*****er" on Twitter last week.

       BBC Newsnight’s Emily Maitlis asked Mr Barnier: “Dominic Cummings called you a ‘lazy, emotional bull*****er’.

       “What did you make of that?

       The Frenchman answered: “I have no comment about Cummings.

       “I never met Mr Cummings, perhaps one time in 10 Downing Street with Johnson.

       “I don’t...I never speak with him.

       He continued: “So I am not sure he knew or knows clearly what happened in the negotiations.

       “So there is no importance for me on Cummings’ comments about me.”

       Ms Maitlis asked: “You don’t think he knew what was going on?

       He replied: “No, no importance.”

       The host asked again: “So why would he say lazy or emotional?”

       Mr Barnier answered: “I don’t know. I don’t know.

       Dominic Cummings took to Twitter to savage a tweet from Andrew Adonis, a former British Cabinet minister

       He said Barnier’s book “My Secret Brexit Diary,” which is about to be released in English, “reinforces my view that Brexit was a catastrophe for Britain — Barnier was better than all Britain’s negotiators put together and ran rings around Lord [David] Frost”.

       However, Cummings did not agree and called out Adonis’ “usual ignorance”.

       He also described Barnier as “emotional, bullshitter, lazy”.

       Dominic Cummings was sacked by Boris Johnson in November last year.