The human rights group will present its report on Thursday during a three-day annual meeting being held in Moscow this week by Kimberley Process, a diamond industry watchdog.
Global Witness says that up to 300,000 carats of conflict diamonds -- gems mined in war-torn areas by terrorist groups in order to raise funds -- leave the West African country of Ivory Coast for neighboring Mali, where they are acquired by global traders and smuggled onto the legal markets.
"Diamonds brought by land from Ivory Coast to [Mali capital] Bamako are purchased by buyers flying in from foreign countries, including from Russia, South Africa, the U.K. and the U.S.," according to the report, a copy of which was obtained by The Moscow Times.
The Kimberley Process, created in 2001 in South Africa, was set up by diamond-producing states to better regulate and license the diamond market in a bid to stem the inflow of gems from terrorist-controlled mines entering the market.
This year, Russia took over as chair for the Kimberley Process, which includes 69 countries. With Finance Minister Alexei Kudrin in attendance on Tuesday, the watchdog passed a resolution to bring the United Nations onboard to look into Ivory Coast's rough-diamond mining industry. "The situation in Ivory Coast remains complicated. It endangers the Kimberly Process," said Nikolai Tolyatnikov, a Russian member of the watchdog's secretariat.
While progress has been made, Global Witness says Tuesday's resolution did not go far enough. More thorough investigation into the smuggling of diamonds is needed to stop the gems reaching smaller diamond polishing centers such as Armenia, an up-and-coming diamond polishing center.
"The Kimberly Process has not yet achieved its aim," said Susie Sanders, a Global Witness campaigner in charge of the report.
Although it meets current Kimberley Process standards, Armenia still lacks adequate diamond trade control, making it vulnerable to conflict-diamond smuggling, she said.
All of Russia's official rough-diamond mining is handled by state monopoly Alrosa, which produces a quarter of the world's supply.
"There are no conflict diamonds in the country," said Alrosa spokesman Andrei Gusenkov, adding that Alrosa could not monitor smuggling operations.
Although Russian traders may be involved in smuggling rings, that does not mean that the gems are destined for the Russian market, said Richard Wake-Walker, a London-based independent diamond expert.
However, illegal gems smuggled through Mali and Liberia reach the markets of Guinea and Sierra Leone, Kimberley Process participants, where licenses are readily for sale. The diamonds can then be traded on the major diamond markets in Belgium and Dubai, the report says.
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