Within minutes of the announcement that the Duchess of Cambridge had gone into labour, excitement broke out on social media as the world prepares to welcome the fourth in line to the throne.

Despite the early hour the topic began trending almost immediately on Twitter, with #RoyalBaby and Kate Middleton the top two worldwide.

While many fans have gathered at the Lindo Wing others are following and reacting to the news online.

In the last week of the election campaign the party leaders were quick to break away from campaigning by sending their best to the royal couple.

David Cameron tweeted: "My best wishes to the Duchess of Cambridge, who is having her second child today. The whole country will wish her well."

Nick Clegg shared the Prime Minister's sentiments, saying: "Best of luck to the Duchess of Cambridge today, as she gives birth to her second child. The thoughts of the whole country will be with her."

Labour leader Ed Miliband said: "I want to pass on my best wishes to the Duchess of Cambridge. My thoughts are with her and the Duke of Cambridge today. I wish them well."

Author JK Rowling had speculated yesterday that the birth may take place today.

She said: "I wonder what odds we'd get on the royal baby being born tomorrow and called Victoria?"

But Twitter user Liz Webb said she was keeping her fingers crossed for a baby girl sharing her name.

"Come on #RoyalBaby. Please be born today and be a princess called Elizabeth," she said.

The jokes are coming thick and fast, with the other big event of this month - the election - getting a mention.

London-based Twitter user WH said: "It's odd for the royals to get involved in an election but good to see Kate Middleton has joined the Labour party. #RoyalBaby."

Referencing a gag from comedy sitcom Friends, Australian journalist Gavin Fernando said: "If it's a girl, Phoebe. If it's a boy, Phoebo. #RoyalBaby."

The jokes are coming thick and fast, with the other big event of this month, the election getting a mention.

Fans across the globe are taking full advantage of technology to ensure they do not miss out on the action.

One self-confessed royalist based in America is excitedly following one of the many livestreams available.

Known in her Twitter bio as Jennifer, and tweeting under the handle @KateWillFan, she posted a picture of the entrance to the hospital and said: "Hello old friend. I've never been so happy to stare at a door."

Campaign group Republic urged the media to keep "a sense of perspective".

Chief executive Graham Smith said: "This may be news, but it's not big news, it's not headline news and it's not news most people are interested in beyond brief curiosity.

"When there's a hugely important election just days away and crises overseas, to spend more than 30 seconds talking about the non-story of a royal baby is a complete over-reaction."

Not everyone is so excited by the news, with some less-than-impressed by the mass hysteria.

Bill York said: "In other news, woman has baby", while another user tweeting under the handle @TravelerDaddy said: "Some of these people really need to get out more."

Another person named Micha questioned those who have spent days waiting at the hospital ahead of the announcement.

"Are those women for real that have been standing outside a hospital for 1 MONTH waiting for a baby to be born," she said, adding a series of shocked emoticons.