Nintendo said today it has sold 400,000 units of the Wii U last week during the console's launch in the United States, according to the company's internal sales estimates. In 2006, Nintendo said it sold 600,000 units of the original Wii console through the first eight days of launch in North America.

"Wii U is essentially sold out of retail and we are doing our best to continually replenish stock," Nintendo of America president Reggie Fils-Aime said in an interview with CNET. "Retailers are also doing their best to get the product to store shelves. But as soon as product hits retail, they're selling out immediately."

Additionally, Nintendo said it sold 300,000 Wiis, 250,000 3DS units and 275,000 DS units during last week.

[Source: CNET]

[Correction: Nintendo sold 600,000 units of the original Wii in North America in 2006 through the first eight days. Not just the U.S. Nintendo sold 475,000 Wii systems in the U.S. in the first 8 days. The story has been corrected above.]