If Johnson wants a deal, Brexit looks set to be delayed, writes Robert Peston

This I think is important. There may be an agreement tomorrow between Brussels and London negotiators on a deal. But no detailed text has yet been shared with the 27 EU leaders and their respective governments.

So, it looks way too late for EU leaders to endorse a formal Brexit deal with Boris Johnson at the EU Council tomorrow and Friday.

Which means the best the UK PM can hope for is a political discussion that sends out a positive message on the prospects for a deal.

Which in turn means that MPs cannot vote on a deal this Saturday, there can be no meaningful vote.

Which in turn means that even if Boris Johnson does not want a Brexit delay, there is no earthly way (that I can think of) that he can avoid one, if he wants a Brexit deal (which he does).

And one other thing. I also can think of no way the European Parliament can scrutinise and ratify the deal - if it is ever done - before 31 October.

So Boris Johnson's pledge to get us out of the EU at the end of the month looks to be for the birds.

His battle cry was "Brexit, do or die". Presumably there was an unspoken third option.

Anyone know what it is?