The International Labour Organisation (ILO) has appealed for global action to ease the plight of hundreds of millions of child workers.

The call came at the start of the organisation's annual conference, which is expected to approve a convention eliminating the worst forms of child labour.

Around 250m children are forced to work to survive. Many of them toil in mines and sweatshops or are lured into the criminal world of prostitution and drug trafficking.

The convention, agreed last year, is likely to remain limited in scope. Calls from activists for it to include access to education are likely to go unheeded.

Poorer countries such as India and Pakistan argue that work itself can be educational and that they cannot afford to offer education to all.

The ILO says the convention will be a historic step forward in the fight against child labour. But that will only happen if countries ratify and implement it. Their record so far has been poor.