GABORONE, May 28 (Reuters) - Botswana's Okavango Diamond Company (ODC) sold 1.02 million carats worth $193 million in the five months to May, 20 percent less than the same year-ago period due to a weaker market and lower output, the firm said on Thursday.
State-owned ODC, which has held four tenders in 2015, is expected to sell 14 percent of the production of Debswana, a joint venture between Botswana's government and Anglo American's diamond unit De Beers.
ODC was established to market a portion of Debswana's rough diamond production as Botswana seeks to develop its own price book through an independent window outside of De Beers' channels.
"Global rough diamond prices have softened since the fourth quarter of 2014, largely as a result of weaker polished prices," ODC Stakeholder relations executive Kutlo Thathana told Reuters.
As per a 2011 agreement with De Beers, ODC's supply of the diamonds from Debswana increases by one percent annually, until it reaches 15 percent by 2016.
Debswana produced 24.3 million carats from its four mines in 2014 and is expected keep production in the 23-26 million range in the short to medium term, Thathana said.
Botswana is the world's biggest diamond producer. (Writing by Zandi Shabalala; Editing by Ed Stoddard and David Evans)