Human trafficking has replaced the drugs trade as the world's largest illegal business, security experts have warned.

The people trade has become a multi-billion dollar business, with millions of men, women and children bought and sold every year, according to the Organisation for Security and Co-operation in Europe (OSCE).

Illegal immigrants risk being sold into prostitution

And it says that the trade is rising, apparently because traffickers feel there are fewer risks involved in trading humans compared with drugs.

The experts meeting in Bangkok argued that not only do the people being smuggled risk their lives, but are likely to end up as prostitutes or cheap labour in sweat shops throughout Europe, the United States and Asia.

The mass illegal movement of people will also pose a major threat to the social, cultural and development of the countries these people come from, delegates were told.

Extremists fear

The warning came as EU leaders gathered in the southern Spanish city of Seville with co-operation to fight illegal immigration top of their agenda.

Millions of people are smuggled around the world every year

EU leaders have been spurred into action by an alarming rise in people smuggling over the past few years and by the electoral successes by the far right in France, the Netherlands and Denmark.

The UK Prime Minister, Tony Blair, said on Thursday that failure to tackle the issue of illegal immigration would play into the hands of extremists.

Mr Blair conceded that previous European agreements had not been implemented, but said the momentum was now such that practical steps would have to be taken.

The leaders are expected to finalise about 50 proposals to cut the number of illegal immigrants entering the 15-nation EU.

Proposals include sanctions against poor nations that fail to co-operate in halting the flow of illegal immigrants.

Other measures include beefing up border patrols, closer co-operation on visas and sending help to Italy, Spain and Greece, which are on the front line of illegal immigrants crossing the Mediterranean Sea from Africa, the Middle East and the Balkans.