De Beers Group has bought up a 50 per cent shareholding of its retail arm De Beers Diamond Jewellers, giving it full control of the business.
The stake was formerly owned by LVMH, the luxury goods group behind Louis Vuitton, Christian Dior, and Moet champagne.
Bruce Cleaver, chief executive of De Beers Group, said: "With its strong brand awareness, consummate diamond expertise and a commitment to responsibility, De Beers Diamond Jewellers is a trusted and industry-leading diamond jeweller.
"More fully integrating the De Beers Diamond Jewellers brand and store network will enable us to deliver an even more differentiated diamond offering, alongside our fast-growing diamond brand, Forevermark."
De Beers Group, which was established in 1888, is part of the mining giant Anglo American. By snapping up the other half of De Beers Diamond Jewellers, it now fully owns a store portfolio comprising 32 outlets, in 17 different countries.
As with many luxury brands, De Beers Diamond Jewellers has been growing its business in China, and has been seeking to attract Chinese buyers in its more established markets such as London, Paris, and, more recently, New York, where it opened a store in December last year.