Lily Allen announces she is pregnant

Lily Allen will go ahead with this Saturday's scheduled performance at the Big Chill festival (Getty Images)

Pop star Lily Allen has revealed she is pregnant, telling her fans: "I can't wait."

The Smile singer, who is due to perform at the Big Chill festival on Sunday, and her painter and decorator boyfriend Sam Cooper are expecting their first child.

Allen, 25, who suffered a miscarriage in 2008, wrote on social networking site Twitter: "Thank you all for all the lovely messages, I'm delighted! I really want to start a family."

Asked if she had told "porkies" in a tweet last month which denied she was pregnant, Allen said: "I wasn't too sure... but now I know and I cant wait."

Her spokesman confirmed: "Lily Allen and Sam Cooper are very happy to confirm that Lily is expecting their first child.

"Lily's professional commitments will carry on as normal, including a scheduled performance at the Big Chill this weekend."

A recent scan revealed the chart topper was three months pregnant.

Allen, daughter of comedian and actor Keith Allen, started dating her builder boyfriend, 32, last summer.

Her pregnancy follows numerous hints that she was retiring from pop music, but last month she took to the stage at London's Wireless Festival, providing support for US rap superstar Jay-Z.

This year she has also been setting up a vintage clothing line, Lucy In Disguise, with elder sister Sarah Owen.

Her pop career has seen her notch two best-selling albums, Alright, Still and It's Not Me, It's You, as well as number one singles The Fear and Smile.

In January 2008 Allen suffered a miscarriage after becoming pregnant by Ed Simons, one half of dance duo the Chemical Brothers.

She recently spoke about wanting children, saying: "I don't think I'm that young to have a baby. My mother had me when she was 23. (Having a family will give me something) more solid, something that exists, that makes me feel more grounded."