Microsoft said in a statement that it remains fully committed to the acquisition and will appeal the decision.while Activision said it will “aggressively work” with the tech firm to reverse it.
“We will reassess our growth plans for the UK,” Activision said. “Global innovators big and small will take note that – for all their rhetoric – the UK is clearly closed for business.”
Activision shares were down more than 10% in pre-market trading in the United States.
The unexpected decision comes after the Competition and Markets Authority (CMA) last month dropped concerns about the deal’s impact on the console market, led by Sony’s PlayStation.
Microsoft attempted to overcome this hurdle by signing licensing agreements with streaming platform owners such as Valve Corp, Nvidia, and Boosteroid.
Microsoft had already offered Sony – a staunch opponent of the deal – a 10-year “Call of Duty” license, in line with a deal to bring the multibillion-dollar franchise to Nintendo’s Switch.
Europe will decide on the deal on May 22. The US Federal Trade Commission also wants to block it.