Saudi investor Prince Alwaleed bin Talal has agreed to buy a $300 million stake in microblogging service Twitter.

The agreement to acquire a "strategic stake" in Twitter followed "several months of negotiations", his company Kingdom Holding said in a statement today.

The Riyadh-based company, controlled by Prince Alwaleed, a nephew of Saudi Arabia's King Abdullah, jumped as much as 8.3 per cent on the local exchange.

Twitter, which lets people send 140-character messages, is enhancing its service to lure more users and make the site more attractive to advertisers.

Prince Alwaleed's investment in the San Francisco-based company comes as Facebook, the world's most-popular social networking site with more than 800 million users, is said to consider raising about $10 billion from an initial public offering.

"Kingdom realizes the importance of social networks like Twitter and their future growth prospects, and decided to benefit from this trend," said Samer Darwiche, an analyst at Gulfmena Investments in Dubai.

Twitter said in August it had raised a new round of funding from DST Global, along with several past investors.

The company aimed to raise about $800 million and was looking to use half the money to buy back shares from employees and earlier backers, people with knowledge of the plan said at the time.

Twitter confirmed the investment in an e-mail, declining to give additional comments.

Prince Alwaleed is the biggest individual investor in Citigroup. His other investments include stakes in General Motors, News Corp and Apple.

The prince was ranked the richest Arab businessman this year by Arabian Business magazine with assets valued at $21.3 billion.

Bloomberg