Stars support Britney at birthday bash

Britney Spears celebrated her 27th birthday today by appearing on US TV show Good Morning America.

The singer performed her new single 'Womanizer' before a number of celebrities delivered recorded messages wishing her well.

John Travolta, Teri Hatcher and Hugh Jackman all sent birthday greetings, while actress Reese Witherspoon said: "You look great, and I hope you have a great day."

However, Spears disappointed the show's host Diane Sawyer by giving limited answers after her performance. Asked where her forthcoming tour starts, she replied: "America", leaving Sawyer to tell the audience the exact location and date.

The presenter later said that she wished Spears would "sit and talk to us".

The popstar was criticised over the weekend for her mimed performance on The X Factor.