Phnom Penh: A Cambodian man who worked for Australian nurse Tammy Davis-Charles has testified he paid US$200 to a village official to obtain a birth certificate for a surrogate baby on behalf of Australian biological parents that police allege was falsified.

Penh Rithy told a Phnom Penh court that Ms Davis-Charles paid him US$600 to arrange birth certificates for single surrogate babies and US$800 for twins.

He also testified that Ms Davis-Charles paid him hundreds of dollars to arrange travel documents so that surrogate parents could take their babies home from the impoverished country.

Police have alleged that Ms Davis-Charles, a former Melbourne nurse and mother of six, was involved in the falsifying of documents, including birth certificates, before she was arrested in a crackdown on Cambodia's then booming commercial surrogacy industry last year.