UK-based mining group Rio Tinto has begun a strategic review of its diamond business that will include exploring a range of options for potential divestment of its diamond interests.

The move is expected to generate nearly $ 4.7bn, with the three diamond mines operated by Rio Tinto being sold to a new owner.

The diamond mines include Argyle in Australia owned by Rio with a 100% interest, Diavik in Canada with 60% and Murowa in Zimbabwe with 78%, as well as Bunder, an advanced diamond project in India with a 100% interest.

Rio Tinto Diamonds & Minerals chief executive Harry Kenyon-Slaney said the diamonds market outlook is very positive, with demand growing strongly and lack of new discoveries limiting supply.

"We have a valuable, high quality diamonds business, but given its scale we are reviewing whether we can create more value through a different ownership structure. This process may take some time," added Harry.

The production from the company’s three operating diamond mines is sold in Antwerp, and it also operates a niche cutting and polishing factory in Perth for the rare pink diamonds from its Argyle mine.