Prince William's wife Kate on Monday gave birth to a baby boy who will one day inherit the British throne, Kensington Palace said in a statement.

"Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 4:24 pm (1524 GMT)," said the statement. "The baby weighs 8 lbs 6 oz. (3.8 kilos)." Kate and her child were both "doing well" and will remain in hospital overnight, it added.

William was present for the birth at St. Mary's Hospital in central London while the queen was "delighted" after hearing of the news, said the palace.

"The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, Prince Harry and members of both families have been informed and are delighted with the news," added the palace press release. Crowds cheered outside Buckingham Palace as the long-awaited news was finally announced at 8:30 pm local time.

Frenzy in London

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Earlier, the London hospital hosting Prince William's wife Kate was the scene of a frenzy after weeks of waiting for the royal baby - while tourists kept an eye out for a big announcement at Buckingham Palace. For the dozens of weary international journalists who have camped for three weeks outside St Mary's Hospital in Paddington, central London, there was relief with the promise, finally, of some actual news to report.

Kate's admittance to the hospital's private Lindo Wing at around 6:00 am (0500 GMT) also brought joy for the handful of hardcore royalists who have camped outside the hospital for several days.

"I'm so excited, like I'm in a washing machine," said John Loughrey, who, resplendent in the red, white and blue of the British flag, has slept on a bench outside the hospital for seven nights.

"I've never been so high! It was such a long wait. I hope it's worth it. I hope it's a girl," he told AFP.

Since July 1, the forest of camera tripods and photographers' ladders that sprang up outside the hospital has been staffed by a handful of highly underworked cameramen sprawled in the sunshine on what has been dubbed the "Great Kate Wait".

But on Monday the sleepy mood vani hed. William and Kate's child is the first British royal baby born into the era of 24-hour news - and despite a likely wait of several hours still to go before the actual birth, reporters were queueing up for endless live dispatches. "We've been waiting for this for 10 days now," said Shanshan Yang from China's CCTV channel.

 "It was a long wait. We didn't show up every day, but now of course we'll stay here til the baby comes."

As the hours wore on without any news, however, the correspondents resorted to interviewing each other.

A large media camp has also sprung up at Queen Elizabeth II's London residence Buckingham Palace, where a formal notice of the birth is to be displayed on a gilded easel at the gates.

As on any glorious summer day in London, hundreds of tourists were gathered at the palace gates to watch the traditional Changing the Guard ceremony. Most were unaware that Kate had gone into labour, but expressed delight when they heard the news.

"We've been waiting for the baby for days!" said Jane Ku, who had come over from Singapore with a group of girlfriends. "We're going to buy all the baby souvenirs, baby dolls and things like that. I'm hoping it will be a boy."

Visitors from countries where the queen is head of state - which along with Britain include 15 realms such as Australia, Canada and New Zealand - were particularly enthusiastic.

"We've been getting updates every morning on Canadian TV and it's great to see that it's a worldwide affair, that everyone's curious about what's happening," said David Wyatt from Toronto, who was holidaying in London with his wife and three young daughters.

"We were wondering whether we were going to be here in London when it happened, and it's wonderful. My family were empire loyalists in Canada and my father's from England. We're proud Canadians."

Connie Sourlatzis, a 30-year-old from Melbourne, said William and Kate had "brought some life back into the royal family".

"I'm a lot more interested in them now than I used to be," she said. "They're really popular in Australia, especially Kate. She's a fashionista. Everyone loves her.

"I've been telling everyone back home that she was waiting for me to get here because she didn't want me to miss it, so I'm really pleased she's gone into labour."

Her boyfriend Josh Killoren was slightly less enthused.

"I'm hoping it's a boy, I'm sick of seeing a girl on the side of our coins," he said, earning a smack from Sourlatzis.

A flood of last-minute bets on Britain's royal baby poured in even as Prince William's wife Catherine was in hospital in labour.

Most of the money was going on the name of the third-in-line to the throne, with one bookie suspending betting on the subject.

"The money really is pouring in. We have taken about £30,000 ($45,000, 35,000 euros) in the last three hours. It's unbelievable," Rory Scott, a spokesman for Irish bookmakers Paddy Power, told AFP.

"The majority of that is on the name. We have suspended betting on the date."

Speculation that the baby is a girl, based on a misheard comment by Kate in March, means girls' names are most popular with the punters.

"There is a clear view that the baby will be a girl so there is lots of activity around girls' names," a spokeswoman for British betting firm William Hill told AFP.

"Alexandra and Charlotte are the most popular."

Other favoured names are Diana, William's mother's name; Elizabeth, after the current queen; and Victoria, after Britain's longest reigning monarch.

Those who think the baby will be a boy have plumped for George and James.

James is the name of Kate's brother but George has been the favourite "from day one", say the bookies.

Bookies say they have taken more than £1 million in total on what they have called the biggest novelty (non-sporting) market of all time.

Bets have come in from around the world with one Austrian man placing £1,000 on a male baby.

Scott said the amount of money is "quite staggering" and compared to what would be placed on English football's FA Cup final.

"We have taken about £10,000 a day over the weekend," he said.

The most bets by volume have been on the name Diana but they have been smaller amounts of money and it has drifted out of the odds, he said.

The date itself seems nearly certain with firms suspending the betting on Monday now that the Duchess of Cambridge is in labour.

In the run-up it was an unpopular choice of day, though.

"The 17th was the most popular. Only five percent of the bets were placed on today - today was an outsider," said the William Hill spokeswoman.

"Everyone seemed to think that the baby would come last week."

Even after the birth there will be no rest for the betting firms, with people now betting on Kate's sister putting in an appearance.

"We are running bets now on the colour of the dress Pippa will be wearing on her first visit to the hospital and how many times Pippa will run the media gauntlet, how many times she will enter in the hospital and who will be holding the baby on the steps. The current favourite is William," Scott said.

There are also bets on the godparents with "the usual suspects - David Beckham, Prince Harry, and Pippa" among the favourites, said the William Hill spokeswoman.

And the betting bonanza could go on for years - firms are already taking wagers on baby number two.