Since taking office on Wednesday and filling his Cabinet with hard-line Brexiteer politicians, Boris Johnson has insisted on striking a new deal with the European Union that would omit the so-called backstop for preventing a hard border between the Republic of Ireland and the British territory of Northern Ireland.

In an email to national governments on Thursday, EU negotiator Michel Barnier wrote that Johnson's demand was "of course unacceptable and not within the mandate of the European Council."

Read more: UK's Boris Johnson promises MPs 'new golden age' after Brexit

"No deal will never be the EU's choice, but we all have to be ready for all scenarios," Barnier wrote. The EU had to be ready for  Johnson giving "priority" to planning for a no-deal exit, "partly to heap pressure on the unity" on the remaining 27 member states, he added.

Juncker, Johnson exchange words

Outgoing President of the European Commission Jean-Claude Juncker confirmed Barnier's comments he spoke with the new British premier on Thursday. "President Juncker listened to what Prime Minister Johnson had to say, reiterating the EU's position that the withdrawal agreement is the best and only agreement possible — in line with the European Council guidelines," Juncker's spokeswoman said after the telephone conversation.

"President Juncker reiterated that the Commission remains available over the coming weeks should the United Kingdom wish to hold talks and clarify its position in more detail," she said.

A spokesman for Johnson's office said the prime minister had told Juncker the backstop would have to be abolished to avoid a no-deal Brexit. Johnson also stated that the withdrawal agreement made between Prime Minister Theresa May and the EU would not pass parliament in its current form.

UK parliamentary opposition

In his email to EU leaders, Barnier  also referred to opposition that Johnson could face in the UK parliament if he tried to force through a no-deal outcome. Barnier referred to the "many strong reactions to the [Johnson's] speech in the House of Commons."

"In this context, we must follow carefully the further political and economic reactions and developments in the UK following this speech," Barnier wrote. "In any case, what remains essential on our side is to remain calm, stick to our principles and guidelines and show solidarity and unity of the 27."

Barnier concluded by saying he was available throughout the summer for talks with the UK, or with EU leaders, should they have questions.

The UK has until the end of October to conclude a withdrawal deal. Many experts predict that the UK risks a severe economic downturn if it leaves with no arrangement in place.

jm/amp (AFP, Reuters)

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