Ladies who lunch, trophy wives, trailing spouses everywhere - it’s time to dust off those CVs, buff up your IT skills and invest in some smart office separates. For no less an authority in this land than the monarch herself has called time on the self-indulgent life of what used to be called the kept woman - that is, pleasurable psychotherapy, Bond Street shopping and light charity work interrupted by Caribbean holidays.

Yes, according to those ever-loyal “pals” of Wills and “royal insiders”, the Queen has intimated that Kate Middleton, Prince William’s girlfriend, should get a job. Not that Buckingham Palace will confirm it: “We do not comment on Kate Middleton. She is a private individual for the time being or until the status quo changes, if it does change,” I am told.

I bet Her Majesty did say it, though. While most women of Kate’s age are putting in long hours at the office and taking on huge mortgages on starter flats or studios, the employment history of the royal girlfriend-in-chief amounts to a brief spell as an accessories buyer for Jigsaw and - er, that’s it.

Unless you count as work the colourful photographs that the 26-year-old graduate is taking of iced cupcakes and fairy-tale unicorn bags and then uploading onto her parents’ mail order website, Party Pieces. For all we know, this is a very demanding position that stretches the gracious Kate (“Call me Catherine”) Middleton to her limits - and to be fair, the photos are really rather good.

Still, what’s blindingly clear to everyone, including Her Majesty, is that far from earning a living and establishing her independence, the young lady is spending much of her time working out in the new Clarence House gym, having blow-drys, stocking up on knee-length skirts and making demure appearances at Sloane nightclubs such as Mahiki.

In other words, Kate gives the appearance of having abandoned all hope of normal life (a life that should, by rights, include a crap job, slutty attire and Krakatoa cocktails) in favour of sitting it out as a “waity Katy” until the magic moment when William drops on one knee and she finally becomes a living, breathing, fairy-tale princess as opposed to one of the frothy tutu-wearing, wand-waving pink moppets of her parents’ catalogue, which is the closest most of us will ever come to royalty.

The Queen must surely feel this is not clever PR. As an 82-year-old monarch who has devoted her life to duty and service, she clearly has little sympathy with the idea that a young woman who might one day be queen should be whiling away the interregnum by hitting Boujis. Indeed, Her Majesty is known to favour the young female royals who “do” something, such as Sophie Wessex and Lady Helen Taylor. Even Fergie, for all her faults, is these days more fairly described as the Duchess of Work than the Duchess of Pork.

So I’m afraid the story rings true. I have no doubt that the Queen - not for nothing is she called the head of the firm - has issued a get-to-work order for two good reasons.

One, the Queen reads the newspapers and meets ordinary people every day. She can’t fail to be aware that the disposable income of the middle and working classes is shrinking - but that the top 0.01% in Britain have seen their incomes rise by more than 500% over a generation. So the gap between the super-rich and royals on the one hand and the rest of her subjects on the other is wider than ever before.

In this credit-crunchy climate - when 99.9% of women are forsaking designer shops for Oxfam or eBay and cancelling holidays and struggling to meet bills - the sight of a princess-in-waiting on perma-holiday is out of synch. Big time. After all, both William and his brother are in the armed services and the other young royals are mostly working parents. (It is with justifiable pride that Viscount Linley describes himself as “a carpenter”.)

Reason two: most very rich people, and especially the Queen, know that a life of pampered idleness, especially one in the bosom of the royal family, is a breeding ground for unhappiness. I’m not thinking of Diana, who was always determined to work with children and the underprivileged, but of the late Princess Margaret, who had so little to do that she filled in time by washing the coral she had collected on holiday in the Caribbean or by sticking the sides of matchboxes onto tumblers (so that she could light cigarettes more easily while drinking whisky).

So if Her Majesty has told William’s girlfriend to get on one’s bike, it is partly because she knows that life will never be the same again for Kate if she joins the firm and that she needs to make the most of her civilian status while it lasts.

One day her prince may come and she might be Queen Catherine. But meanwhile, being plain Kate Middleton is her last chance to be a wage slave, to lead from the front, to do her own washing-up and to show rich, kept women that they can do something more worthwhile with their lives. She mustn’t blow it.

- The Joseph Rowntree Foundation reported last week that there was a desperate need for cheap housing in rural Wales. Meanwhile, the Commission for Rural Communities suggested that with the right sort of support from government, the rural economy could double its contribution of £325 billion to gross domestic product. So, as night follows day, I was invited to talk about second home ownership on the Jeremy Vine show on BBC Radio 2.

This is because I once made the mistake of writing an article for this newspaper about owning a second home. Desperate at the time to talk to other second-home owners, I approached first a Guardian columnist, then the head of a big charity and finally the head of the Second Home Owners’ Club. All owned second homes. Not one of them was willing to be quoted. I was on my own.

So when the producer called, I stiffened. There is no more thankless role to play than apologist for those who - in that smug phrase - “divide their time” between Hampstead and Norfolk, or Notting Hill and Exmoor. “Only if you plug my new book,” I said reluctantly (since you ask, it’s called Shire Hell).

As soon as I started to go on about tax rebates and affordable housing, the angry calls and e-mails started flooding in.

I never want to pronounce again on behalf of Britain’s second-home owners - especially as I bought mine from my father and don’t feel I deserve the ire.

Perhaps Cherie Blair (who has about six residences at last count) could do it instead.

rachel.johnson@sunday-times.co.uk

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