The [UK government] signed up for Microsoft's super-special zombie OS support service--aka a Custom Support Agreement--last year, but a recent meeting of government Technology Leaders decided enough is enough. A post [blog.gov.uk] on the Government Technology Blog says the Leaders "took a collective decision to not extend the support arrangement for 2015".
A support agreement that ended in April was therefore not renewed.
[...]An undiscussed number of agencies are still running XP, at least on some machines, leading the government digital service to suggest "We expect most remaining government devices using Windows XP will be able to mitigate any risks, using the CESG guidance."
[...]As we've reported [theregister.co.uk], agencies including the Metropolitan Police, the [National Health Service], and [Her Majesty's Revenue and Customs] are still to finish XP migration projects.
Related: Microsoft Ends Support for Windows XP [soylentnews.org]