Sunak looked like he was getting an excruciating telling off by a headteacher as Starmer grilled him at PMQs - analysis by Olivia Utley

To say that the Prime Minister was on the back foot when PMQs began today would be a gross understatement: Rishi Sunak was firefighting on almost innumerable fronts.

Before the exchange took place it had been rumoured that the Leader of the Opposition would use all six of his allocated questions on the Nadhim Zahawi affair. But Sir Keir was far more astute than that.

For the first 10 minutes of the exchange he focussed his questions — which were forensic and pithy — on the Zara Aleena case and the state of the probation services after “13 years of Tory rule”.

In choosing to prioritise this issue, which objectively, of course, is far more important to the country than the tax arrangements of the Conservative Party Chair, Keir Starmer managed to present himself as the statesman of the pair, more interested in the state of the country than the sordid goings on in SW1.

Thanks perhaps to Sunak’s youth and diminutive physique, from my position in the gallery the exchange even at times had the feel of a headteacher ticking off a troublesome pupil.

When Starmer finally did turn his attention to the Zahawi scandal, it was clear that Sunak and his team have been strategising hard over the past few days.

Where last week the PM defended Zahawi to the hilt, this week he was at pains to distance himself from the Party Chair, referring to him as “the minister without portfolio” rather than the customary “my honourable friend”.

The substance of the PM’s defence of his own decision to appoint Zahawi is, in essence, that he was told by the cabinet office that though questions about his Chairman's tax affairs had indeed been raised, the matter had been resolved and was free to (re)appoint the YouGov founder to the cabinet.

This, of course, begs the question of why Sunak didn’t probe further, given his repeated assertions that he would be PM to restore integrity to public life. But it also raises awkward questions for the Cabinet Office, and in particular the embattled cabinet Secretary Simon Case - who also oversaw the Richard Sharp affair.

In Whitehall the blame game has well and truly begun.

Sunak was at his strongest when defending his own decision to stick to “due process” and launch an investigation rather than take the “politically expedient” route and get rid of Zahawi at the first hint of trouble.

There have been murmurings on the Conservative backbenches that a more experienced politician than Sunak would have acted decisively and cut the cord long before now. But today, Sunak did a decent job of presenting his commitment to playing it by the book as a strength rather than a weakness.

Nadim Zahawi’s political career may well not survive the week. And then the spotlight will turn on Rishi Sunak.

Will the Prime Minister’s attempt today to cauterise himself from his Party Chairman be enough? Or will Westminster see it as simply too little, too late?