International humanitarian agency the United Nations has warned that thousands of women are being pushed towards the sex industry as a source of income after at least 20 Cambodian garment factories shut down over the last four months.

According to news agency Reuters, Cambodia's labour minister Nhep Bunchin said there has been a spate of closures since Cambodia joined the World Trade Organisation in September, putting thousands out of work.

Noeleen Heyzer, executive director of UNIFEM, the UN's women's agency, said that there was a risk that unemployed women would migrate to other countries, either to enter into prostitution, or to become illegal workers.

Cambodia's garment industry has expanded rapidly over the past few years and now employs approximately 265,00 workers, most of whom are young women.