DE BEERS CEO Philippe Mellier has predicted the group’s diamond production for 2013 should match the 27.9-million carats produced in 2012, "subject to market conditions".

Production for the first half of 2013 amounted to 14.3-million carats – nearly 1-million carats up on the 13.4-million carats produced in the first six months of 2012 despite production problems at two of the group’s most important mines – Venetia in Limpopo and Jwaneng in Botswana.

The Venetia open-pit mine was flooded by the heavy rains that hit northern Limpopo in January, while operations at Jwaneng are still recovering from the major pit-wall failure that occurred in 2012.

Mr Mellier said ore-mining shortfalls at Venetia were to some extent compensated for by processing ore stockpiles, while recovered grades at the Jwaneng and Orapa mines in Botswana had improved.

He said: "With full recovery from the Jwaneng slope failure and Venetia mine flooding expected during the second half, De Beers continues to anticipate full-year production will recover to be broadly in line with 2012, subject to market conditions.

"De Beers expects moderate growth in diamond jewellery demand in the remaining six months of 2013, supported by improving sentiment in the US market and continued growth in China, albeit at a lower rate.

"Conditions in India and Japan remain more uncertain due, in part, to the continuing volatility of their currencies, which is expected to affect growth in dollar terms.

"Overall, despite the fragility of the global economic recovery, macroeconomic conditions are generally supportive of global growth in the polished diamond market in 2013 at levels slightly above 2012."

Mr Mellier said diamond sales had remained steady at $3.3bn, unchanged from the first half of 2012, although De Beers had increased prices by 6% during the first half of 2013 after lowering them by 12% in the second half of 2012.

Asked whether this was putting undue pressure on the profit margins of the diamond-cutting firms, Mr Mellier replied: "We feel we have responded responsibly to market conditions. Diamond prices now are lower than they were a year ago."

De Beers’ underlying operating profit contribution to Anglo American increased by $322m to $571m, driven primarily by Anglo American’s increased shareholding from August 2012.