Some 10.5 million children are believed to be working as domestic labourers worldwide, according to a new report.

The International Labour Organization (ILO) says that many work in conditions that are sometimes verging on slavery.

The report, released to mark the World Day Against Child Labour, suggests that 6.5 million of these children are aged between five and 14 years old and over 71% are girls.

The report also says many are subjected to physical and sexual violence.

Some are sent into work to supplement the family's income or to pay off debts. They are often denied access to education.

The ILO says domestic child labour remains largely hidden and is calling for new international regulations.

Because the work takes place within homes, it it is difficult to regulate.

"The child is working, but is not considered as a worker, and although the child lives in a family setting, she or he is not treated like a family member," the report says.

"We need a robust legal framework to clearly identify, prevent and eliminate child labour in domestic work, and to provide decent working conditions to adolescents when they can legally work," said Constance Thomas from the ILO.

The report also stresses that domestic work is an important source of employment, especially for millions of women.

"Domestic workers of all ages are increasingly performing a vital task in many economies" added Ms Thomas.