Nintendo's Shigeru Miyamoto's told Edge that Microsoft and Sony's rush to motion with Natal and Move is "threatening" behaviour.
"Whenever something we have created and presented is followed by copies, we always feel it is threatening," said the dev legend.
"More than that, we’re concerned that others are trying to do something similar for the sake of it. It’s not encouraging to Nintendo."
The exec was answering a question on whether or not she saw parallels between the uptake of motion controllers and the "borrowing" of analog sticks in the PlayStation generation.
Both Natal and Move will release towards the end of this year, and both will feature heavily at E3 later this month.
Nintendo will show its latest hardware, 3DS, at the LA event.