Published: 12:35 PM October 8, 2019 Updated: 6:09 PM September 17, 2020

Boris Johnson meeting Angela Merkel in August. His most recent proposals to adjust the backstop raised eyebrows among EU negotiators, it has been reported. Picture: Stefan Rousseau/PA Wire/PA Images - Credit: PA Wire/PA Images

EU negotiators were so unimpressed by Boris Johnson's new Brexit proposals they asked if there had been some mistake, it has been revealed.

Boris Johnson's recent bid to secure a Withdrawal Agreement with the EU has been greeted with enormous scepticism by leaders.

But as the government's chief 'sherpa' David Frost returns to Brussels to continue negotiations, new reports have emerged on just how tone deaf the proposal was to the EU.

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Article 1 of the proposed agreement would commit both the EU and the UK to agree never to introduce checks at the Irish border - which is what the EU wants in order to protect the Good Friday Agreement.

Yet the proposal would put a customs border between the two Irish nations and a second regulatory one in the Irish sea, without specifying how this could be achieved without physical border infrastructure.

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The proposal also offers the Northern Irish Assembly - which has not sat for three years - a veto on the agreement, which takes any say out of the EU's hands and has the potential to undo the principle of Article 1.

The UK also insists on continued access to EU databases for cross-border trade, and wants small businesses excluded from customs checks, prompting concerns about smuggling.

A statement from an unnamed Number 10 source - widely assumed to be Dominic Cummings - has reacted bullishly to the early objections from EU leaders, threatening to put uncooperative EU countries to the back of the queue for future negotiations.

It is unclear how this would work as the EU negotiates as a bloc.