Liz Truss prepares to enter the lion’s den of No 10, besieged on all sides

The new prime minister’s less-than-emphatic victory weakens her from the start

Liz Truss’s margin of victory was not quite decisive enough to give her the kind of authority she needs as she enters office facing the most daunting situation that has greeted any recent prime minister.

Rishi Sunak did better than the opinion polls of Conservative members predicted, although not quite well enough to launch immediate speculation about how he would be readying his next leadership bid while he waited for his opponent to fail.

He won 43 per cent of the vote, four points higher than the best figure predicted for him by the pollsters – Opinium Research, which was closest to the result last time, put Sunak on 39 per cent in its final poll, carried out between 8 and 13 August.

So Truss’s victory speech lacked the excitement of an emphatic result, and was as halting as some of her worst performances in the early stages of the leadership campaign. It was so underpowered that the audience of MPs and activists, as keen as a Soviet audience to applaud anything the leader said, missed its cue to clap for Boris Johnson who is, Truss told them, “admired from Kyiv to Carlisle”.

She will make another speech in Downing Street tomorrow afternoon, when she returns from an audience with the Queen at Balmoral, and then she will face the House of Commons for Prime Minister’s Questions at noon on Wednesday.

Keir Starmer offered a preview of his welcome for her in a TV clip responding to her election result, saying that she appeared to be copying Labour’s policy of freezing energy prices but without any way of paying for it.

This is not how a “Thatcherite” prime minister might expect to be greeted by a socialist opposition. Starmer’s first words were a criticism of Truss for her failure to raise corporation tax, because she has promised to cancel Sunak’s planned rise next year. That means Labour is going to accuse the new Tory government of fiscal irresponsibility, increasing borrowing rather than increasing the windfall tax and corporation tax to pay for help with energy bills.

Truss’s second dilemma, now that she has presumably decided on a plan, is when to announce it. Can she go into the Commons on Wednesday without having at least announced the main points? Starmer will then ask where her plan is, having promised during the leadership campaign that there would be help for people from “day one”. She can hardly say: “Wait and see.”

But if she does set out the outline of her plan on Tuesday night or Wednesday morning, Starmer can either accuse her of copying Labour’s plan but paying for it in a way that will spook the markets, or of failing to offer the universal help that Labour has called for.

Either way, the Commons is going to be a hostile environment. Opposite her, Starmer, who has been working on his speaking style rather more successfully than she has, has seized the initiative with his plan to fix energy bills at current levels, with the Labour benches in high spirits behind him, buoyed by national opinion polls.

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Behind her, there will be not just Sunak, itching to say, “I told you so”, but also Johnson, whose ambition to return as prime minister one day is the worst-kept secret at Westminster. I assume that neither of them will actually be in the chamber on Wednesday, or indeed on most days, but their presence will be felt.

Not only did her margin of victory among party members fall short of expectations, but both sides of the Commons know that she is the first prime minister in modern parliamentary politics who (probably) did not have the positive support of a majority of her own MPs.

She may say to herself that Margaret Thatcher was underestimated by her opponents, inside and outside her own party. Now we are going to start to find out if she is indeed made of the same metal.