The world's two biggest diamond producers De Beers and the Russian state-owned Alrosa have agreed to scale down a diamond distribution deal in response to EU competition concerns.
Alrosa had agreed in 2002 to sell rough stones to De Beers worth 600 million euro ($800m) every year for five years, but this will now be gradually reduced to some 200 million euro ($275m) per year over a period of six years.
De Beers also has promised not to buy Alrosa diamonds on the secondary market, according to the Financial Times.
The Anglo-South African De Beers is the largest diamond mining company worldwide with over 40 percent of global gem diamonds produced from mines in South Africa in partnership with governments in Botswana, Namibia and Tanzania.
The Russian state-owned company Alrosa is the world's second largest diamond producer with about 20 percent of the world's rough diamond output.