Traffic, the wildlife trade monitor, released the report before the biennial meeting of the Convention on International Trade in Endangered Species of Flora and Fauna in Zimbabwe.

The report found Hong Kong traders had been illegally supplying Japanese demand with small pieces of ivory, chops or 'hankos'. They are sent by mail, courier or sold direct to tourists.

Executive director of the World Wide Fund for Nature Hong Kong, David Melville said dynamics of the trade had changed from large carved pieces to small chops. '[They are] very easy to conceal to put in your pocket, briefcase, suitcase or send in the mail.

'There is certainly evidence to indicate that people are acting as couriers taking ivory out of Hong Kong to maybe Taiwan or Japan.' Exports of less than five kilograms of personal ivory pieces do not require a permit. Mr Melville said all exports should require a licence.

A stream of ivory seizures to and from Hong Kong indicated the trade continued, and suggested China was a growing market, he said.

Stockpiles of ivory in the territory have dwindled from 463 tonnes in 1990 to 286 tonnes.

'We are looking at reductions in stockpiles from an average 20 tonnes a year which seems very large just for domestic consumption,' Mr Melville said.

'What seems to be the link holding all these various countries together is Japan.' Agriculture and Fisheries Department senior conservation officer Cheung Chi-sun said there had been few seizures of illegal ivory.

He denied the proposal to trade ivory between Africa and Japan would increase smuggling.