The Brexit summit last night was supposed to provide clarity. Instead, it has simply delayed the final decision to another day.

The UK could still leave with no deal at the end of May, at the end of October, or anytime in between. The EU27 were also clear that there would be no renegotiation of the withdrawal agreement, which concerns citizens’ rights, the financial settlement and the controversial Irish border backstop.

This has led some MPs to argue that the UK should just leave and start from scratch. The logic goes that the EU’s rigid sequencing of Article 50 – namely that there can be no negotiations about the future relationship until the withdrawal agreement had been passed – would no longer apply in a no-deal situation. Instead, the UK and EU27 could discuss their future relationship immediately and make any financial settlement contingent on the final outcome.

But this is wishful thinking. “No deal” would not make the most salient issues go away – and it is not clear that the UK would be in a better position to get the EU to change its mind.

There is no reason to disbelieve EU assertions that the withdrawal agreement would be a precondition of new talks.

No deal would not make the most contentious issues go away. The EU’s chief Brexit negotiator, Michel Barnier, has already made clear that the EU would insist on settling all the issues in the withdrawal agreement before turning to future discussions. The EU would still want the UK to settle its exit bill, to guarantee citizens’ rights and to sign up to an insurance policy on Ireland. Moreover the EU would reckon that the UK coming back to the negotiating table after a cold shower of no-deal reality would be readier to bend than before, whoever is prime minister. Under no deal, the UK would be negotiating from a position of weakness.

What’s more, it is not clear that the UK would be in a position to change the EU’s mind. While the EU27 have put in place some unilateral measures to mitigate the worst effects of a no deal, for example allowing flight carriers to continue carrying out their services, the EU has made clear that these would be time-limited and would not be extended. And these are far from comprehensive.

Whereas the UK plans to adopt a relatively permissive regime for EU traders wanting to keep doing business in the UK, the UK government’s own technical notices make clear that many sectors would need to new authorisations from the EU to keep on trading, as we become a third country not covered by any new agreement. As Raphael Hogarth notes, the UK would in effect become a supplicant to the EU27 – and because UK negotiators would be under time pressure to negotiate alternative arrangements, they may be forced to accept the EU’s negotiating demands.

There are also broader political considerations. EU27 leaders are worried that if they chose to row back on their red lines to suit the UK, anti-EU politicians in their own countries may decide this is a good tactic to adopt to force the EU’s hand in internal EU negotiations – for example on the eurozone and refugee and asylum policy. Over one-third of seats in the new European Parliament are expected to be won by Eurosceptic candidates. So even if the EU27 did want to meet the UK halfway, they probably would not for fear of setting a precedent for politicians across the EU27 to follow.

No deal would make redundant more than two years of painstaking and time consuming negotiations. Any lingering goodwill among EU27 would be squandered. UK politicians need to think carefully about the risk that a no deal presents: a UK that is grappling with the complications of no deal may have no other choice but to accept the negotiating requirements from a more frustrated and inflexible EU.