Liz Truss's and the Tory Party's future 'all depends on Boris,' writes Robert Peston

By sacking Kwasi Kwarteng and ditching most of her tax cuts and her energy subsidy, Liz Truss has bought herself a stay of execution.That much is clear from my conversations with Tory MPs who know the mood of their party.Their working assumption is that there will be no coup against her in the coming few days, that her MPs - demoralised and in shock - will bide their time till at least 31 October. They want to see the new chancellor Jeremy Hunt's additional tax rises and spending cuts - and the revised state of the public finances - before sacking or backing her.As I said on News at Ten last night, her greatest source of strength at the moment is very little about her, and all about the factionalism of her opponents.It is that her most obvious successor, Rishi Sunak - the losing candidate in the recent election to be Tory leader, who had the virtue of warning that her tax policies would be a disaster - is cordially and less cordially detested by perhaps 50 or 60 Tory MPs.They denigrate him as a "socialist", for having put up taxes - and can't bring themselves to see that the recent financial crisis strengthened his case, not theirs.Others of them - of whom Nadine Dorries is the most conspicuous - will never forgive him for what they see as his leading part in undermining their hero Boris Johnson.That is why influential Tory MPs keep saying the same surprising thing to me: "what happens next all depends on Boris".The point, they say, is that Truss has the unique distinction of turning the deficit in the polls that was created during the Partygate phase of Johnson's premiership into a yawning chasm.They doubt - following the catastrophe of her mini budget - she stands any chance of reducing Labour's 30 odd percentage point lead to a gap that would allow the Tories to contemplate even respectably narrow defeat at the next election.Tory Party extinction is an outcome they are unable to exclude.So what Tory MPs are asking is whether Johnson can bring himself - in the words of one ex minister - "to put his personal animosities to one side and do what's necessary to save the party".

What do they mean?Here is what one Tory MP said: "I don't think Boris harbours ambitions to return to office, or at least not now. The only credible successor is Rishi. So the question is whether Boris can bring himself to tell his supporters to lay down their arms and stop their campaign against his former chancellor?"There is probably no chance of a Tory revival if Truss were replaced via a fractious leadership contest, with the party's ideological and personality divisions angrily displayed.And maybe the post-Brexit transformation of the Conservative Party into an ideological one, so far from its pragmatic history and traditions, means that there is no scope for it to rebuild this side of a general election.But if anti-ideological Johnson were capable of publicly saying he no longer bears a grudge against Sunak - and frankly that looks highly implausible - maybe the Tory Party will somehow not tear itself apart in the coming weeks.

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