Nokia is currently building new Windows Phones that feature dual-core ST-Ericsson chips.

The Finnish company is expected to debut its Windows Phone offerings later in the year with Microsoft’s Windows Phone 7.5 “Mango” software. Forbes reports that some future devices will be powered by silicon from ST-Ericsson. Carlo Bozotti, the Chief Executive of European semiconductor maker STMicroelectronics, revealed the news in an interview with Forbes. Bozotti also claims that Nokia is planning 12 Windows Phones for 2012.

The first ST-Ericsson chipset inside a Nokia Windows Phone will be the U8500. The silicon is a dual-core system-on-a-chip which is also available inside the Samsung Infuse 4G and Sidekick 4G. Forbes labels the devices as “Windows Phone 8″ which is expected alongside Microsoft’s Windows 8 desktop operating system. The information backs up rumors that Microsoft may unveil a full chassis 2 hardware specification for its next generation Windows Phones. Nokia has allegedly been working closely with Microsoft on the new chassis specification to ensure they are able to create cheaper Windows Phone devices for the mass market.

Nokia’s Windows Phone devices are currently labelled with “W” (for Windows). The first handset is expected to be a variant of Nokia’s X7 device. The prototype is equipped with a WVGA display, Qualcomm QSD8250 chipset and 8MP camera. Nokia is also rumored to be launching a dual-core N8 variant with a 12MP camera, QWERTY touchscreen candy bar phone and a cheaper touchscreen device with less expensive body materials.