Oprah and Barbara battle it out for Pippa

Chat show hosts Oprah Winfrey and Barbara Walters are engaged in a 300,000-pound bidding war for Pippa Middleton's first ever TV interview in the US.

The younger sister of the Duchess of Cambridge, who is about to start promoting her upcoming book about how to be the perfect hostess, is considered to be the pair's "dream guest" for 2012.

Winfrey is said to have told staff at her OWN network to "pull out all the stops" to secure the interview while Walters is reportedly pressuring bosses at ABC to offer a six-figure sum for the interview.

Both want to secure Middleton as a guest for an hour-long special.

"The big guns see Pippa as the big-name interview of 2012... Oprah and Barbara Walters are hot on the case," Fox News quoted a source as telling the Sunday Mirror.

Middleton, who will donate any fee she receives to charity, rose to fame after her show-stopping appearance at Britain's royal wedding in April, when her sister married Prince William.

Last year, the professional party planner signed a publishing deal to write a book on party etiquette, for which she reportedly received a 400,000-pound advance.