Boris Johnson has promised to take the UK out of the EU on 31 October “deal or no deal”, “do or die”. The prime minister says he can strike a different deal from Theresa May’s, which must include scrapping the Northern Ireland backstop. European leaders insist, however, that an entirely new deal is not on offer. So what now?

Could Johnson pull a rabbit out of the hat and strike a new Brexit deal despite the apparent impasse?

He says yes. But Johnson and the EU are miles apart. The taoiseach Leo Varadkhar said last week that going back to the drawing board was “totally not in the real world.” Some Johnson backers believe, however, that if he hangs tough he could persuade the EU to give him an additional form of words, a legal codicil on the Irish backstop, that he could then triumphantly wave as evidence of a European surrender, but that the EU would say changes little. This would still need to pass through parliament, however, and Tory hardline Brexiters might well see it as just words, and rebel in sufficient numbers to block it.

If he fails to get a deal, could he just take the UK out with no deal on 31 October?

In theory yes. Johnson said outside No 10 last Wednesday that the country must prepare for no deal. But he would run into huge opposition from MPs of all parties. Opponents of no deal will spend the summer plotting how to prevent him doing so. When they return to parliament in September they will try to amend Brexit-related legislation, mandating him to seek an extension if no deal has been reached before October. Labour could also table a no-confidence vote in the government and enough Tory Remainers, including Philip Hammond, Dominic Grieve and Kenneth Clarke, could back it. They have all indicated they would be prepared to bring down a government that tried to push through no deal against parliament’s wishes.

Could Johnson shut down (prorogue) parliament to prevent it legislating to block no deal?

He has not ruled out doing so. The legal default position is that if there is no deal, and the UK has not asked to revoke article 50 or been granted a further extension, then we leave on 31 October with no deal. But MPs of all parties have already flexed their muscles to prevent the prorogation of parliament to get no deal. Earlier this month they passed an amendment to a Northern Ireland bill by a majority of 41 to make prorogation more difficult; 315 MPs backed it and 274 were opposed. The anti-Brexit campaigner Gina Miller is also planning legal action to prevent prorogation.

Could he call an autumn general election to get Brexit through?

Yes. Many MPs believe Johnson is deliberately setting the bar high with the EU so he can return from talks over August with EU leaders saying they simply won’t budge – and that he therefore needs a mandate to leave with no deal on 31 October. He would need the support of two thirds of MPs to call an election. Tories would be ordered to vote in favour and Labour would have to back an election too, having argued for one consistently. If he did this when parliament returns on 3 September, there would be time to go to the country before 31 October.

Could there still be a second referendum on Brexit?

Yes. Supporters across the Commons have not given up hope. MPs could amend Brexit legislation to insist on an extension, and say that the time be used to hold an election or second vote. Alternatively, were Johnson to strike a deal, they could pass an amendment to legislation required to get the deal through parliament, making its passing conditional on approval by the British people.