Windows 7 users upgrading to a more powerful version of the operating system will be charged more than twice as much in Britain than in the US in some cases, Microsoft has revealed.

Windows 7 is scheduled for release on 22 October, and the Windows Anytime Upgrade scheme sets prices for those who want to switch between one version of the OS to another.

Those upgrading to Windows 7 Professional will pay £120. However, US buyers taking the same upgrade path will pay $90 - that's £54 according to Monday morning's exchange rate. Businesses are already expecting to pay more for corporate licences than consumers. 

Other deals for Brits include the Windows 7 Starter to Professional upgrade - which costs £120 in the UK and £69 in the US. There are six upgrade paths in total and all cost considerably more in the UK than US.

Windows 7 Anytime Upgrade Pricing (US pricing in brackets)

Windows 7 Starter to Home Premium: £70 (£48)
Windows 7 Starter to Professional: £120 (£69)
Windows 7 Starter to Ultimate: £140 (£99)
Windows 7 Home Premium to Professional: £120 (£54)
Windows 7 Home Premium to Ultimate: £125 (£84)
Windows 7 Professional to Ultimate: £85 (£78)

Also on Friday, Microsoft announced that it is abandoning plans to ship Windows 7 without Internet Explorer in the hope that European antitrust regulators will okay its proposal for a 'ballot screen' allowing users to select different web browsers with the OS.