Early Wii U sales are steady although not matching those of the console's predecessor, according to Nintendo's top executive, Satoru Iwata.
Nintendo's president told Reuters: "At the end of the Christmas season, it wasn't as though stores in the US had no Wii U left in stock, as it was when Wii was first sold in that popular boom. But sales are not bad, and I feel it's selling steadily."
Iwata also said that producing two Wii U models was a new challenge for the company, and that it had failed to anticipate the level of demand for the premium version of the console.
"It was the first time Nintendo released two models of the game console at the same time ... and I believe there was a challenge with balancing this. Specifically, inventory levels for the premium, deluxe package was unbalanced as many people wanted that version and couldn't find it," he said.
North American Wii U sales hit 400,000 units during the console's first week of availability, Nintendo has claimed, while Japanese Wii U sales totalled 638,339 units between the system's December 8 launch in the country and December 30, according to Famitsu publisher Enterbrain.
In a recent investor note, Sterne Agee analyst Arvind Bhatia claimed Wii U sales over the holiday season at major US retailer GameStop were 'below expectations'. He suggested Wii U stock at the retailer remained 'abundant', and that software attach rates were "low", although he didn't offer any solid figures.
"Our conclusion is the Nintendo Wii U launch has been slightly disappointing," Bhatia said.
Nintendo's Osaka-listed shares have dropped 15 per cent since the Wii U launched.