Oxfam, which has produced the report, says new controls introduced under Labour's more "ethical" foreign policy have not closed loopholes which allow the arms trade to continue unchecked.
The charity is calling for tighter controls to ensure arms shippers do not divert goods to undesirable groups after they reach Britain. It has also produced new evidence that false "end-user certificates" are easy to obtain.
The research, previewed in The Independent in October, also calls for rules to prevent British companies getting round export licensing regulations by allowing their weapons to be made abroad.
The report Out of Control says in May this year 32 tonnes of Army-surplus goods requiring an export licence were flown out of Kent International Airport by Occidental Airlines. The plane was scheduled to fly to South Africa after refuelling in Nigeria, but was empty when it reached its final destination.
The goods appeared to have been transferred to Kent from Zaventem near Ostend the previous day via the Channel Tunnel. Customs Officers gave loading permission for the flight believing its cargo consisted of civilian items.Although the load did not contain arms, it still required an export licence because it contained military equipment and clothing.
In July 1997 the Belgian government refused permission to Occidental Airlines for a very similar consignment destined for Burundi. In September 1997 the shipment was moved to a warehouse in Zaventem.
As part of its research, Oxfam tried to buy an end-user certificate to prove it could be done easily. Although it has not named the country involved, the charity says it received its certificate within a few days. It has called for such certificates to be checked at each transit point, for British embassies abroad to monitor sales to sensitive destinations, arms brokers to be licensed and production of arms abroad for British companies subjected to the same controls as goods made here.