Britain’s antitrust regulator has announced that it will block Microsoft’s acquisition of Activision Blizzard over concerns that it would impede competition in cloud gaming. Microsoft’s commitment to providing access to Activision’s “Call of Duty” franchise to major cloud gaming platforms would not effectively address these concerns. Microsoft’s president, Brad Smith, has stated that the company will appeal the decision, while Activision plans to work with Microsoft to reverse it. The deal is the largest technology-related acquisition to be blocked by Britain’s Competition and Markets Authority. Europe will make a decision on the deal by May 22, while the US Federal Trade Commission is also looking to block it.