Michel Barnier, the EU's chief Brexit negotiator, has suggested Boris Johnson is merely "pretending to negotiate" Brexit as his European counterparts await details of his proposals to replace the Irish backstop, a key part of the withdrawal agreement.

The UK prime minister has repeatedly promised to try and remove the backstop, a measure designed to ensure that no new border checks emerge on the border between Ireland and Northern Ireland, claiming that it is anti-democratic.

But Johnson's negotiators have so far only presented the EU with a draft of the withdrawal agreement with the backstop scrubbed out, and are not planning to take their plan to the EU until October, weeks before the Brexit deadline.