Microsoft on Monday fired a shot in the looming videogame console war with the announcement that its new champion - Xbox One - will launch in November in 21 countries.

The US technology titan staged a private media event the morning before the start of a premium E3 conference here to provide more details about the next-generation home entertainment hub it revealed in May.

Japan-based rival Sony was to provide a deeper look into its next-generation PlayStation 4 console late Monday at its own gala gathering.

The successor to the Xbox 360 will be available for $499 in the United States, £429 in Britain and 499 euros in Europe.

As promised, Microsoft focused on its core audience of gamers at the E3 presentation of a box designed to become a hub for films, television shows, music and other home entertainment streamed from the Internet.

"Xbox One is designed to deliver a whole new generation of blockbuster games, television and entertainment in a powerful, all-in-one device," said Microsoft president of interactive entertainment Don Mattrick.

"Our unique, modern architecture brings simplicity to the living room and, for the first time ever, the ability to instantly switch across your games and entertainment."

The beefed-up hardware is powered by software that allows for instant switching between games, television, and Internet browsing. Microsoft-owned Skype was also integrated for online group video calls.

Kinect motion and sound sensing accessories accompanying the consoles recognize users; respond instantly to commands spoken in natural language, and even detect a person's pulse.

"Our creative teams are already using Xbox One to push boundaries and possibilities for more immersive gaming experiences," said Ubisoft senior vice president of sales and marketing Tony Key.

"While there has been focus on the non-gaming types of entertainment the Xbox One supports, video game fans can rest assured that Xbox One is set to be a very powerful gaming device."

France-based Ubisoft plans to release a half-dozen titles in the year after Xbox One launches in November. Those titles include the next installment to the blockbuster 'Assassin's Creed' franchise and a promising new 'Watch Dogs' game in which players must use hacker skills in a smart city to prevail.

Microsoft teased gamers with the premier of a video trailer for a version of beloved science fiction shooter game 'Halo' tailored for play on Xbox One.

Other hot titles previewed included 'Battlefield,' 'Minecraft,' and 'Dead Rising.'

Microsoft has sold some 77 million Xbox 360 consoles since they hit the market in late 2005. Console rival Sony has sold about the same number of PlayStation 3 consoles, which was introduced a year later.

Meanwhile, Nintendo sold nearly 100 million Wii consoles, which became hits due to innovative motion-sensing controls after their debut in 2006. However, demand for Nintendo's recently released Wii U consoles has been disappointing.

People attending the industry-only E3 gathering will be able to try out Xbox One and PS4 consoles on the show floor.

While next-generation consoles will dominate E3, digital play has changed considerably from when their predecessors arrived some seven years ago.

Smartphones and tablet computers have powered a boom in games available for free, with money made from ads or in-game purchases.

"I think the console players will continue to be in denial about what is really going on," said Clive Downie, who spent 17 years at videogame titan Electronic Arts before becoming chief at mobile games platform company DeNA.

"People's time is being eroded, so console sales will be eroded by people playing on mobile devices."