Saudi billionaire Prince Alwaleed bin Talal, an investor in some of the world’s top companies, has bought a stake in Twitter for $300 million, gaining another foothold in the global media industry. Alwaleed, a nephew of Saudi Arabia’s king estimated by Forbes magazine in March to have a fortune of $19.6 billion, already owns a 7 percent stake in News Corp and plans to start a cable news channel. The Twitter stake, bought jointly by Alwaleed and his Kingdom Holding Co investment firm, resulted from “months of negotiations,” Kingdom said.

Explorer Gulf Keystone Petroleum is not in talks with U.S. oil major Exxon Mobil Corp about a 7 billion pounds ($10.9 billion) bid, a source familiar with the Kurdistan-focused group’s thinking said on Monday. The Independent on Sunday newspaper reported that Exxon was considering making an estimated 800 pence per share bid – five times Gulf Keystone’s closing share price on Friday. The report, which drove Gulf Keystone’s shares up as much as 24 percent on Monday, said the company’s board had discussed Exxon’s interest a fortnight ago. But a source familiar with Gulf Keystone’s thinking said there were no talks with Exxon.

European Goldfields, which has agreed to a C$2.5 billion ($2.4 billion) takeover by Canadian group Eldorado Gold, is hoping to keep an investment deal with Qatar’s sovereign wealth fund as a fall back option. Qatar Holdings agreed in October to provide a $600 million project financing loan to European Goldfields, which has development stage assets in Greece and Romania, in its first investment in a gold miner. It also provided a $150 million loan note and a related warrant issue, and became a major shareholder, with a 9.9 percent stake. Eldorado’s strong balance sheet means European Goldfields is unlikely to need the cash from Qatar if the takeover goes through — but it does need two-thirds of shareholders to back the deal when they vote in February.

Etihad Airways is taking a stake of almost 30 percent in Germany’s Air Berlin, becoming the first Gulf carrier to challenge European legacy airlines by putting cash on the table to gain scale. Abu Dhabi-based Etihad will spend about 73 million euros ($95 million) to buy new shares of Air Berlin, raising its stake to 29.21 percent from just below 3 percent, and will lend the German carrier $255 million, the two companies said on Monday.