The sex trade has been compared to slavery

American delegate Donna Hughes from the University of Rhode Island told the conference that the global trade in women and children as commodities for the sex industry is estimated to be worth up to $12bn a year.

The sex industry itself makes $52bn annually.

Men create the demand, she said, and women are the supply - often women from countries characterised by poverty, unemployment, war and political instability.

Children

Because of its relatively low risk and high profits, criminals and organised crime groups are increasingly attracted to sex-trafficking in preference to the trade in drugs or arms.

The women and children involved are getting younger because clients assume they are free of HIV infection.

In short, global sexual exploitation is a human-rights crisis affecting an estimated four million women and children per year.

Putting the trade in context, Ouasila Tamjali from Algeria blamed a society which puts money, consumption and the market at the top of its scale of values.

She criticised the International Labour Organisation for officially recognising the sex industry, emphasising its economic importance and its contribution to the gross national product of the countries involved.

She compared the fight against human trafficking to the fight at the end of the nineteenth century to abolish slavery and said it was incompatible with the dignity of the human person.

Domestic violence

This is a hard-hitting conference which has discussed violence against women in all its aspects - as a result of armed conflict, in the home, the sex trade - with discussions on cultural and religious practicesn due later.

Violence against women in armed conflict was discussed

On Wednesday sociologist, Liz Kelly told the conference that one in four women suffers domestic violence at some time in their lives.

In some countries, that figure is higher than one in two, and one in 10 women is currently suffering from some form of abuse, she said.

Ms Kelly told the BBC that fighting sexism would help reduce abuse of women.

"Violence against women happens because of gender inequality," she said.

While not ruling out the theory that men abuse women because they are threatened by the changes inherent in globalisation, Ms Kelly said that violence against women is an age-old problem.

"It is not something new that happened with globalisation," she said.