The US regulator said the deal, which would be the largest in the history of the video games industry, could “substantially lessen competition” in the sector.

The move comes a few weeks after the UK blocked the deal over concerns it would stifle competition, but the EU approved the deal in May nonetheless.

The FTC said in a court filing that a “preliminary injunction is necessary to […] prevent interim harm” while the regulator determines whether “the proposed acquisition violates US antitrust law”.

Microsoft’s proposed takeover needs approval from regulatory bodies in the UK, the EU and the US. A trial in the US will now commence in August.

Activision Blizzard is responsible for some of the world’s most popular video game franchises, including Overwatch, Candy Crush and Call of Duty.