Police in Britain and Vietnam have signed an agreement aimed at trying to break up networks smuggling Vietnamese people into the UK.
The agreement, announced by the British Embassy in Hanoi, will see police sharing information on people and gangs suspected of people trafficking.
The move follows protests over plans to deport hundreds of Vietnamese children who had entered the UK illegally.
Some of these were thought to have been taken to Britain by criminal groups.
Drugs and prostitution
The embassy said police, particularly in London, were increasingly concerned about organised crime in the Vietnamese community in Britain.
A spokesman said there were concerns a small minority was involved in crimes such as illegal immigration, drugs and prostitution.
Many of those being targeted for these crimes were children, he added.
Last month a coalition of children's rights organisations criticised government plans to deport as many as 500 children back to Vietnam.
A delegation from the Home Office recently visited Vietnam to discuss the matter but the embassy said no agreement on the children's future had yet been reached.
It is hoped the new agreement will reduce the number of such cases in the future.