Joseph Kony, the group's warlord leader, has been indicted for war crimes by the International Criminal Court and is being hunted in Uganda.

The report follows a speech by former US secretary of state Hillary Rodham Clinton last year in which she highlighted how militant groups including al-Shabab "fund their terrorist activities to a great extent from ivory trafficking".

Ivory, most of which ends up on the market in Hong Kong and the mainland, provides these terrorist groups with hundreds of thousands of dollars that are used to finance militant activities, said Andrea Crosta, executive director of the Elephant Action League and a former security and intelligence consultant.

"People must realise that behind a simple ivory trinket lies a long chain of blood and criminality," said Crosta, who participated in an 18-month undercover investigation into the syndicates behind the illegal trade.

"I was offered ivory, weapons and even uranium. Ivory buyers need to understand the kind of people who engage in the trade," said the Italian conservationist.

China is the world's largest consumer market for ivory and many of the shipments transit in Hong Kong before being moved to the mainland. Estimates of the amount of illegal ivory destined for the Chinese market range from 60 to 90 per cent of the total supply leaving Africa.

Based on seizures, Crosta believes the actual figure is close to 80 per cent. Earlier this year Operation Cobra II, an Interpol-led international crackdown on wildlife crime, found that 200 out of the 350 cases investigated involved China.

The price of ivory in China has tripled to US$2,100 per kilogram over the past four years, making the increasingly scarce tusks a lucrative source of revenue for terrorist and militant groups.

One of the most organised of these groups is al-Shabab, a Somalia-based cell of al-Qaeda.

With an estimated strength of between 4,000 and 6,000 militants, the group is responsible for a host of killings, including the assassination of a Somali lawmaker on Thursday and the deaths of 67 people in an attack on a Nairobi shopping mall in September.

Unlike the Lord's Resistance Army and the militia in Sudan - both of which actively hunt and kill elephants for their tusks - al-Shabab positions itself as a middleman and a buyer.

After receiving an order, al-Shabab will trigger its network of contacts in Kenya and Somalia to obtain a consignment, then use its smuggling expertise to move the ivory onto ships in Mombasa or Dar-es-Salaam, Crosta said.

"In Africa, al-Shabab is considered a good buyer - it pays well, pays on time and there are no jokes. Usually they arrange pick-ups in the middle of nowhere and move the ivory quickly offshore in skiffs, like with drugs," Crosta said.

They have the capacity to buy between one and three tonnes of ivory every month and make huge profits that they then use to buy weapons, he added.

The issue will likely feature on the agenda when nations meet this week at the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) in Geneva.

Also up for discussion is the possibility of implementing a decision-making mechanism (DMM) that would provide pro-trade countries such as China and a number of African countries an avenue to legally buy and sell ivory.

"The DMM is a disaster waiting to happen to the last remaining African elephant populations," said WildAid campaigner Alex Hofford. "It has been proven, time and again, that the legal ivory trade provides a cover for the illegal ivory trade."

In 1999 and 2008, China was granted one-time legal purchases of ivory consignments overseen by an official state body. However, campaigners say ivory dealers are laundering illegal smuggled ivory into the much smaller legal market.

"The fundamental issue is that the abuse of the legal market is key," said Environmental Investigation Agency executive director Mary Rice, who will be at this week's meetings in Geneva.

"China's position has been very strong in reducing demand for illegal ivory, but it still encourages legal ivory," said Rice.

An official on the Chinese delegation to CITES did not respond to inquiries.

The discussion has never been more critical, with African elephants facing extinction within a decade.

"The illegal wildlife trade is a serious criminal industry worth more than £6 billion (HK$80 billion) each year. While threatening the future existence of a whole species, it devastates already vulnerable communities, drives corruption and undermines efforts to cut poverty," said Martin Walley, International Wildlife Trade Campaign coordinator at the British Foreign and Commonwealth Office.

Ivory seizures in Hong Kong reached an all-time high of 8,041kg last year, up 43 per cent from 2012 and 300 per cent from 2003, according to figures from the Agriculture, Fisheries and Conservation Department.

A spokesman for the customs department said it would maintain close contact with overseas and mainland enforcement agencies to prevent smuggling, but said there was "no evidence" Hong Kong had become a transit point for the ivory trade.

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