The US Federal Trade Commission (FTC) has criticised Microsoft for increasing the price of its Xbox Game Pass. 

In a letter to the US Court of Appeals, the agency said that charging more for the subscription service is "exactly the sort of consumer harm" that it predicted would happy when it was opposing Microsoft's record-breaking acquisition of Activision Blizzard. 

In September of this year, there are price increases across the board and the introduction of a new Game Pass Standard tier that leaves out Day One launches. The console version of the subscription service is also being axed, leaving players on Xbox hardware to go for the much more expensive Game Pass Ultimate tier. In fact, it is 81% more expensive for that level – assuming they want Day One titles – and 17 per cent more expensive to 'upgrade' to the new Standard tier. 

The fact that these changes are going to take place around the time that the next Call of Duty game comes out is also cause for concern, the FTC says. 

"Microsoft's post-merger actions thus vindicate the congressional design of preliminary halting mergers to fully evaluate their likely competitive effects, and judicial scepticism of promises inconsistent with a firm's economic incentives," the agency wrote.