Nintendo of America boss has stuck the knife in to following the release of the Go handheld, stating that the system has a "fundamental concept problem".

The outspoken exec wonders what the real "benefit" of the digital-only handheld is, presumably shaking off concerns that the device could be a threat to the DS.

"I have the utmost respect for all our competitors, but it's interesting to try and answer the consumer question of 'What's in it for me?' in that product," the exec teased, speaking to The Washington Post.

Fils-Aime added that Nintendo aren't planning a rival mobile device to Apple's iPhone: "We don't have a desire to get into the phone space. We think the game business is competitive enough."

By Luke Guttridge