Smartphones running Microsoft's Windows Phone 7 are set to hit the UK on October 21.
The technology giant told Neowin.net it plans to launch the OS at an event in New York on October 11, with handsets hitting European shelves 10 days later.
The website also revealed Microsoft will partner with a London-based radio station to promote Windows Phone 7.
All five of the UK's major mobile networks: 3, Orange, O2, T-mobile and Vodafone, will stock handsets running Microsoft Windows Phone 7, along with high-street retailers The Carphone Warehouse and Phones4U.
"Following our announcement at Mobile World Congress that Orange will be our lead partner, it is wonderful now to have all of the UK's network operators supporting the launch of Windows Phone 7," said Alex Reeve from Microsoft.
However, those expecting the handsets to support tethering, or the ability to let users connect their phones to a computer to access the internet via a cellular network, with the phone serving as a modem, will be disappointed.
Despite comments made by Brandon Watson, director of developer experience for Windows Phone 7, during a podcast last week, Microsoft has confirmed the function won't be available.
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