THE EU’s chief Brexit negotiator has warned that the UK needs to be realistic if it wants an orderly agreement for leaving the EU.

This week the UK’s negotiator David Frost told MPs that Brussels’s negotiating mandate would “need to evolve” in order for a deal to be reached by the end of the year or else the UK would abandon talks.

But Barnier said today that such changes are “out of the question”. He demanded “more realism in London in the near future if they want an orderly agreement to withdraw from the single market and the customs union”.

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Lashing out at Frost’s claims, he said: “I would remind you that the United Kingdom is leaving the internal market and the customs union … it’s not us leaving the United Kingdom.

“A third country, the United Kingdom, will not dictate the conditions of access to our market for British goods, services, data or for workers and businesses … We remain sovereign. This is my mandate.”

Addressing the issue of the creation of a “level playing field” after Brexit, Barnier said: ““What astonishes me a lot about the British position is that Prime Minister Johnson himself acknowledged [the need for rules of fair competition] in the Political Declaration [on the future relationship] he signed. We negotiated this with him and with David Frost in October, step by step, line by line and comma by comma.”

The negotiator added that reaching a deal before the end of the year will be “very difficult, but it is possible”.

The UK has rejected the possibility of extending the Brexit transition period until the coronavirus pandemic subsides. If they were to seek an extension it would need to be done by the deadline in five weeks’ time.

Barnier went on: “The British have not understood, or they do not want to understand, that Brexit has consequences for them.”

However, he concluded: “We wish to conclude a partnership and balanced agreement with this great, friendly, neighbouring and allied country … But that will never be at the expense of the single market, European consumers and European business, as the British are trying to achieve.”