Windows 9 and Windows Phone 9 will be released in preview format between the first and second quarter of next year, according to a report, Digital Spy said.

Myce has uncovered a leaked Microsoft document hinting that its next-generation operating systems will launch sometime between April and September 2015.

Firm details about Windows 9 have not been disclosed, but Microsoft has been tipped to ditch the tile-based interface introduced with Windows 8.

The company has also been rumoured to scrap its Windows RT tablet operating system in favour of a unified platform that works with both slates and smartphone, the end result of which could be Windows Phone 9.

Microsoft rolled out Windows Phone 8.1 in April, introducing a raft of new features such as a notifications centre, universal app support and the Cortana personal assistant.

The firm also released Windows 8.1 Update to improve support for mouse and keyboard users.