Cameron's wife wants to dress like Gwen Stefani

One is a flamboyant California-born singer who is known for exposing her midriff and has created a distinctive fashion label inspired by Japanese designs.

The other is the wife of the leader of Her Majesty's Opposition who is usually photographed in sensible outfits designed for comfort.

But in a moment of sartorial wistfulness, David Cameron's wife, Samantha, has admitted a secret desire to dress like the singer Gwen Stefani.

Mrs Cameron, 36, told the fashion magazine Harper's Bazaar that Stefani was her alter ego, but added: "I've always wanted to dye my hair blonde. Every time I see her, I go, God, I wish I looked like that!"

Mrs Cameron also revealed that she did not have "huge amounts of spare cash" to spend on designer clothing.

"I'm a working mum. We have to pay for child care. I don't have huge amounts of spare cash to spend on designer clothing. I think all working mums are a bit like that. You feel poorer than you've ever been," she said.

Her predilection for high street clothing from shops including French Connection and Topshop may give her a "fresher" look than politicians' wives who clad themselves in designer wear, she added.

However, she was willing to spend on key items, such as a favourite pair of Dolce & Gabbana heels, which she "wore to loads of weddings and which fell apart from all the dancing".

She revealed that she was "not an urban, combat-pants kind of person. I'm not such a wacky dresser that I'm likely to have my tummy hanging out anyway. And I never wear anything much above the knee."

Speaking about her life in next month's issue of the magazine, Mrs Cameron, who is the creative director of the Bond Street stationery company Smythson, said her motto was to "breathe deeply and don't shout at my husband".

"[Shouting] is normally what I do, just to kind of let it all out. I think that most wives do," she added.

She said they did not hang out with "loads of politicians" and that her husband "does most of the cooking" at home.

"He's quite a big Jamie Oliver fan. At the moment, we're into one-pot cooking, where you shove all the vegetables and meat in the pot, stick it in the oven, and two hours later - wow, it's delicious!" she said.