The World Diamond Council is meeting in London to discuss moves to crack down on the illegal trade in gems mined in war zones - so called blood diamonds.

I'm confident that we will be able to come up with a type of system that will be workable

WDC Chairman Eli Izhakoff

Proceeds from the sale of blood diamonds are used to fund some of Africa's bitterest conflicts, including wars in Sierra Leone and Angola.

Pressure has been mounting on the industry to find a way of stamping out trafficking in the gems.

The WDC's talks will focus on a proposed tracking scheme under which diamonds mined in conflict-free zones would be given a certificate of origin.

Once the scheme - due to be formally launched next month - is implemented, every diamond offered for sale will have to be accompanied by a certificate to show that it is conflict-free.

But critics say the plan does not go far enough.

They argue that once a diamond has been processed, it will be very difficult to determine its origin.

Crackdown

World Diamond Council chairman Eli Izhakoff told the BBC's World Business Report that the support of governments is essential to the plan's success.

Forty governments are involved already, and another thirty are expected to join.

"I'm confident that we will be able to come up with a type of system that will be workable," Mr Izhakoff said.

"But putting the certification system in place clearly is going to make it extremely difficult for anybody to try to deal in this type of diamond.

"Anybody who is trying to sell diamonds better have proof where those diamonds come from."

He adds that people will not be able to sell diamonds and say "I got them from my grandmother."