A woman campaigning on behalf of well-endowed ladies has bought a share in Marks and Spencer in the latest round of a battle over its surcharge on bigger bras.

A woman campaigning on behalf of well-endowed ladies has bought a share in Marks and Spencer in the latest round of a battle over its surcharge on bigger bras.

Beckie Williams, founder of Facebook group Busts 4 Justice and a 30G herself, said she took the step after her efforts as a customer hit a brick wall.

Protesters want Marks and Spencer to introduce a "one price fits all" policy and end its "unfair" practice of charging an extra £2 on bras above a DD cup.

When Ms Williams, 26, received an e-mail saying the policy would not be changed, she bought a £3.40 share to have the chance to confront chairman Sir Stuart Rose at the next annual meeting in July.

She said: "I was surprised and very disappointed when I got the e-mail. It wouldn't have been a massive concession for them to do it.

"They won't listen to me as a customer but they might listen to me as a shareholder."

Ms Williams, a writer from Brighton, pointed out that other lingerie shops do not make people pay more for larger bras.

"It's ridiculous," she said. "You don't do it for other items of clothing so I don't understand the logic."

Marks and Spencer said it offered "the most comprehensive DD+ collection and one of the most competitively priced on the high street" but that an extra charge was required for the work involved in making larger bras.