Xbox boss Phil Spencer has opened up more on the heavily-rumoured Xbox Game Pass streaming device, codenamed "Keystone".

Although there were plans to have the streaming stick/box on the market this year, he revealed that when a prototype product was built, it turned out "more expensive than we wanted it to be".

There is still an intention to produce a product in the future, but only if it can hit a price point of $99 to $129.

Speaking to The Verge's Decoder podcast, Spencer explained that the cost made the team turn its attention elsewhere for now: "We decided to focus that team's effort on delivery the Smart TV streaming app," he said.

"In order for a streaming-only box to make sense, the price delta to [Xbox Series] S has to be pretty significant. I want to be able to include a controller in it.

"I think you've got to be $129/$99 - somewhere in there - for that to make sense."

The Xbox CEO had already revealed that plans for Keystone had been shelved for now - somewhat ironic considering we got a glimpse of the prototype on his shelf in a Twitter post. He said in October that a release could now be "years away".