Kate Middleton will soon be considered an “icon” to lesbians, the novelist Sarah Waters says.

Waters, who wrote lesbian novel Tipping The Velvet, told the Daily Telegraph that Prince William’s fiancée appeals to lesbians in the same way Princess Diana did to gay men.

Speaking at the Man Booker Best of Beryl Prize in Soho, she said: “There is something quite earthy about her which, I think, lesbians will like.”

On Miss Middleton’s appeal to gay men, she said: “Of course, they will be drawn to her glamour, so I think she will do very well for all sorts of people.”

The princess-in-waiting and Prince William have been urged to support marriage equality by gay rights campaigner Peter Tatchell, who has organised a rally outside Buckingham Palace on Easter Monday.

He said: “We plan to deliver a giant wedding card to William and Kate. As well as wishing the royal couple every happiness, we will highlight the fact that William and Kate can marry, but same-sex couples can’t.”