Saudi Prince Alwaleed bin Talal and his investment company, Kingdom Holding, have announced a $300 million (£194m) investment in micro-blogging site Twitter.
The investment represents a 3.75 percent stake of the San Francisco-based company, which was valued at $8 billion (£5.2bn) in October, and follows several months of negotiations, according to Kingdom Holding.
"Our investment in Twitter reaffirms our ability in identifying suitable opportunities to invest in promising, high-growth businesses with a global impact," said Prince Alwaleed in a statement.
Prince Alwaleed is a media mogul and one of the world's richest men. In September he announced the forthcoming launch Alarab, a pan-Arab news channel, saying the television network will promote freedom of speech.
Kingdom Holding also holds a 29.9 percent stake in the Saudi Research and Marketing Group, which publishes several leading newspapers and magazines including the Asharq Al-Awsat newspaper and Al Eqtisadieh, as well as holding approximately 7 percent of News Corporation's Class B Common Stock.
The Twitter investment suggests a new focus for Kingdom Holding on social media. Networks such as Twitter and Facebook played a crucial role in spreading information and organising protests during the revolutions that rocked Libya, Tunisia and Egypt earlier this year.
In Egypt, the government went as far as shutting off access to Twitter, after it became a live platform for protesters to share information on where to meet and what to do. For many it became the primary source of news, and the only tool for Egyptian people to express their views on the ruling power.
"We believe that social media will fundamentally change the media industry landscape in the coming years," said Kingdom Holding's Executive Director of Private Equity and International Investments. "Twitter will capture and monetise this positive trend."
Rumours have been circulating for some time that Twitter is building towards an initial public offering (IPO). Earlier this year it closed a $800 million funding round led by Russian venture capital firm Digital Sky Technologies (DST), which has previously invested heavily in social networking firm Facebook.
Meanwhile, the Wall Street Journal recently reported that Facebook hopes to raise $10 billion in an IPO that could value the company at more than $100 billion (£64bn). The newspaper reports that a Facebook offering of $10 billion would be the largest ever IPO by any technology or Internet company.