Angelina Jolie's adoption papers for her son Maddox were reportedly faked by a local aid worker.
Maddox and Angelina Jolie
The 'Maleficent' actress took on the care of the 15 year old in 2003, and Mounh Sarath, 51, has now claimed he signed official documents in Cambodia naming him as the father of the boy in order to speed up the process and provide a local address, though there is no suggestion Angelina knew of this.
He said: "In court documents, Maddox is still my son. She never cleared this up.
"She had to change his name, so the only way was for me to do it. I said he's my son."
At the time of Maddox's adoption, the US had imposed tougher restrictions on adopting children from Cambodia because of fears of trafficking.
And Mounh, the director of an aid charity, says he still has power of attorney over Maddox and has fallen out with Angelina.
He told The Sun on Sunday newspaper: "I would be happy if Cambodia didn't see her again."
Maddox's adoption was arranged by agent Lauryn Galindo, who was later jailed after falsifying names, birth dates and places of birth of Cambodian children she helped to place with US families.
Angelina - who also has kids Pax, 13, Zahara, 12, Shiloh, 10, and eight-year-old twins Knox and Vivienne with estranged husband Brad Pitt - has previously insisted she went to "great lengths to ensure Maddox did not have a living birth-mother in Cambodia."
She added: "I would never rob a mother of her child. I can only imagine how dreadful that would feel."
The 41-year-old star recently directed 'First They Killed My Father', which is about the genocide that took place under the communist Khmer Rouge regime from 1975 to 1979 in which around 1.7 million Cambodians died from starvation, disease and execution, and admitted making the film had made her understand her son's birth family even better.
She said: "This country means a great deal to me, this country has been through so much. This war affected every single individual here, and I wanted to understand myself. I don't know much of Maddox's birth parents, but I believe they would have gone through this war.
"I wanted to understand this country in a deeper way, and bring this story of Luong Ung who's a dear friend of mine."
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