(IDEX Online) - De Beers CEO Al Cook has written an open letter to G7 leaders urging them to adopt the World Diamond Council's (WDC) proposal to outlaw Russian diamonds.It is one of four frameworks being considered - the others are from Belgium, India and France - to enforce sanctions following Russia's invasion of Ukraine in February 2022.The G7 nations, responsible for 70 per cent of global diamond sales, are expected to sanction Russian goods from 1 January 2024, but have yet to announce how those sanctions will be enforced."In pursuit of a collaborative, coherent and collective solution that supports the aims of the G7, we have joined with 22 diamond industry organisations through the World Diamond Council to progress the 'G7 Diamond Protocol' proposal," says Cook (pictured) in his letter, dated 19 October.He says De Beers "fully and unequivocally supports the objectives of the G7 countries to prohibit diamonds of Russian origin from entering their borders".The company has developed Tracr, its own blockchain-based traceability solution, and is now partnering with Sarine, the Israel-based diamond tech company to create a digital platform that could support the G7 aims.But he acknowledges that there is currently no single technology-based platform that could meet all its requirements.Representatives of the G7 nations - Canada, France, Germany, Italy, Japan, UK, US (and the EU) - were meeting at the end of last week to discuss the technicalities and legalities of preventing goods, primarily from Alrosa, entering the supply chain.The WDC, supported by De Beers, is calling for a self-regulated ban, with spot checks, on +1.0-ct goods, with sellers declaring they are not Russian, and setting up mechanisms to segregate them from non-Russian stones.Belgium is proposing mandatory third-party blockchain technology to certify the provenance of all polished diamonds above 1.0-ct.India says its manufacturers should register with the government for exports of +1.0-ct goods under a self-regulating system. And an industry group in France proposes that sellers declare the origin of round, white +1.0-ct polished stones, with annual, independent audits.