Spears is said to have given birth by Caesarean section

The 23-year-old pop star announced the news on her personal website.

She said in a statement to her fans: "Everyone is happy, healthy and doing wonderful". No name for the baby has yet been announced.

Photographers had been waiting outside the hospital in Los Angeles after reports she had undergone a Caesarean section on Wednesday.

Spears and husband Kevin Federline were said to have been taken to the UCLA Medical Center, Santa Monica, under police escort, earlier in the day.

The US Weekly report said that Spears gave birth just before 1300 local time (2100 BST).

Spears and her husband revealed the news on her website

It also quoted unidentified sources claiming the child would be called Preston Michael Spears Federline.

Speculation

Reports published earlier this week claimed Spears had given birth on Sunday.

But the rumours were subsequently denied by her UK publicist.

"Britney Spears has not given birth," he said. "She's not even in hospital. The baby is due some time in the next month."

Spears married dancer Federline, 27, in September 2004 after they had been together for just six months.

She confirmed her pregnancy in April following months of feverish tabloid speculation.

Federline has two children by his ex-girlfriend, actress Shar Jackson, one of which was born after he and Spears started dating.

In the October issue of Elle magazine, Spears said she was looking forward to motherhood.