Efforts to avert all-out war in eastern part of the Democratic Republic of Congo are doomed as long as negotiators ignore the role of the area’s lucrative mineral trade in fuelling the violence, according to anticorruption advocates and development officials.

They say that the deployment of thousands more United Nations peace-keepers to the region would be fruitless if armed groups continue to profit from the illegal trade with the connivance of international corporations.

Armed groups, including the Congolese Army and Tutsi rebels led by General Laurent Nkunda, have profited from the illegal trade of minerals such as coltan and tin ore for years, with British, Canadian, American and Belgian companies among their best clients.

Efforts to break that link have been stymied by Western governments unwilling to loosen their grip on the trade and made more difficult by the emergence of China as a big economic player on the continent. Rebels under General Nkunda’s control dismissed ceasefire calls made at yesterday’s emergency regional summit in Nairobi because, they said, it failed to address any of their demands – including the cancellation of a $9 billion (£6 billion) mining and infrastructure deal between China and the Congolese Government in Kinshasa.

The European Union said it regretted that the summit did not adopt measures to curb illegal mining. The Chinese deal gives China access to vast reserves of copper and cobalt in return for a project to link eastern Congo to Kinshasa by rail for the first time. General Nkunda complained that the deal would “line the pockets of a few politicians while the Congolese people would see no benefit”.

But advocates say that a host of foreign companies and governments are complicit in fuelling the violence by continuing to profit from the trade.

A 2002 UN investigation to name and shame companies involved, and consider sanctions until the trade could be cleaned up, foundered on international reluctance to lose a foothold in the trade. “Governments have been ignoring the issue and doing their best to paper over the war economy, to dampen down criticism of their companies and keep the minerals flowing,” Patricia Feeney, of the British-based lobby group Rights and Accountability in Development, said. “Unless we are willing to disrupt the supply chains, this remains a self-perpetuating illegal war economy.”

Britain is the only country to have censured companies – Afrimex and DAS Air – for unethical conduct in breach of international guidelines after intense pressure from the anticorruption group Global Witness and concerned MPs. At least another dozen identified by the UN have gone unrebuked.

The US has refused to examine any of its cases, while Belgium has exonerated its companies. German and Austrian companies, among others, remain accused of continuing to source minerals from mines in eastern Congo controlled by armed groups. China, the most recent entrant to the scramble for Africa, remains outside international guidelines on ethical trade.

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