Watching Gisela Stuart, Labour MP, ardent Leave campaigner and British citizen, make the case for Vote Leave on the BBC last night, this was Alan Sugar’s judgement:

It’s a tactic straight out of the playbook of some of the world’s nastiest regimes: “She’s foreign. Look at her original foreign surname. How dare she poke her foreign nose into our business?”

His intent was quite clear – to deny that Gisela has the same right as any of us to express her view on the future of the country which we share. As Nadhim Zahawi responded to Sugar: “That is disgraceful. She is as British as you are.”

Imagine if a Leave campaigner had done this – pro-EU campaigners would be doing their nut, launching petitions all over the place, writing open letters to newspapers about racism and Michael Crick would be chasing every red coach in sight in the hope of doorstepping Boris or Gove about the disgraceful behaviour of one of their own.

Of course, Sugar’s now trying to argue that in fact he was just suggesting Stuart is hypocritical to argue for control over migration, because she is an immigrant herself. For a start, that isn’t what he said at all – he rejected her right to “tell us British what to do” at all, not just on a specific topic.

But even his new account of his own argument doesn’t hold water. Stuart isn’t arguing against any migration taking place, she’s arguing for democratic control of our migration policy. It’s hardly inconsistent for her to argue that all of us should have the power to decide the future policies and laws of our own country. Knocking on doors in South London in recent weeks, I’ve found she’s far from alone in this view – among naturalised Brits, EU migrants, Commonwealth citizens and many others.

It was a poisonous, ignorant and deeply personal attack on an honourable individual. Stronger In have denounced Sugar’s comments as “entirely unacceptable”, but appear to have forgotten that he is an official spokesman of their campaign. In fact, a mere 13 minutes after his tweet about Stuart, they posted a video of him promoting their case.

I’ve written already about the disappointing way in which the pro-EU campaign have failed to live up to their own rhetoric about a “kinder” tone of campaigning. Now another opportunity presents itself to demonstrate that they are willing to pay these claims more than lip service. They should sack Sugar today, and make clear this bile really is as “unacceptable” as they claim.