Surface tablet sales have reportedly fallen short of Microsoft's targets.
According to multiple Bloomberg sources, the company has made an underwhelming start in its bid to crack the fast-growing tablet market, selling about 1.5 million Surface devices.
Microsoft reportedly ordered about three million Surface RTs, but is said to have sold just over a million since the model launched in October 2012.
And Surface Pro sales are believed to stand at about 400,000 units following the model's release last month.
In comparison, Apple sold 22.9 million iPads in the quarter ended December 31, 2012. iPad accounted for 51 per cent of the 128.3 million tablets shipped worldwide last year, according to research firm IDC.