Yahoo has announced that it is shutting down chat rooms used by child predators on its chat service.

The firm has reached an agreement with the attorneys general of New York and Nebraska to allow it to implement controls over chat rooms where users link up with children, view them on webcams and arrange meetings.

Most of the known offending rooms were being created under Yahoo's 'Schools and Education' category.

Yahoo took the decision to suspend all user-created chat rooms in June, and is still deciding whether to reinstate the facility.

If the company does allow user-created chat rooms, it will screen them for sexual content under the terms of the new agreement and remove them within 24 hours if they are deemed offensive.

The agreement is the first of its kind and could lead to similar arrangements, according to New York Attorney General Eliot Spitzer.

"We need to be vigilant to protect our children," he said. "It is imperative that parents, industry, prosecutors and lawmakers work together to identify and address possible threats, and that we teach our children to protect themselves from those who would do them harm."

In June Yahoo removed or barred the posting of approximately 70,000 user-created chat rooms whose names suggested that they facilitated illegal conduct, including promoting sex between adults and minors.

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