By KELVIN CHAN
AP Business Writer
LONDON (AP) — Microsoft’s plan to buy video game company Activision Blizzard faces a potential setback after British regulators demanded the companies come up with concessions to ease competition concerns about the blockbuster deal. The Competition and Markets Authority said it was worried the $69 billion deal would hurt rivals by restricting their access to Activision Blizzard games. It also worried that the combined company would stifle competition in the emerging cloud gaming market. The authority gave both companies five days to come up with proposals to address its concerns, otherwise it would escalate its investigation with more scrutiny. The all-cash deal is set to be the largest in the history of the tech industry.