Update: UKIE tells VideoGamer.com that the charts published this morning "included in error an unverified figure for Modern Warfare 3". This statement doesn't, however, indicate that the sales figure is inaccurate.
UKIE added: "The 2m units and £83.1m figures are currently unverified and may change."
Original story: Activision's Call of Duty: Modern Warfare 3 sold just under two million units during its first five days on sale in the UK, according to data released by Chart Track.
The record-breaking game - 6.5 million units in the US and UK combined on day one - failed to outsell last year's Call of Duty: Black Ops, down 1.6 per cent. However, revenue for the title is 1.5 per cent up over Black Ops at £83.1m.
Modern Warfare 3 is now the highest grossing opening week of all time for any entertainment title, outdoing the opening weekend box office of the last four Harry Potter films combined.
Sales for the title were heavily skewed towards the Xbox 360, accounting for a large 59 per cent of total units, compared to 55 per cent for Black Ops. PS3 took 40 per cent of sales.
Those of you wanting to know our verdict on the game, should click straight onto our Call of Duty: Modern Warfare 3 review. If you're a little rusty on what's happened so far in the Modern Warfare franchise, check out our comprehensive story so far feature.