We are very grateful to have him in our lives

Jolie and Thornton

The move followed reports that infants were being bought by illegal networks from destitute mothers and sold to orphanages for adoption.

Applications made before December were still being processed on a case-by-case basis to make sure that the children were genuine orphans, a US embassy spokesman said.

Maddox's case was among "hundreds of others in the pipeline", he said.

Jolie and Thornton said they first saw the boy in November during a trip to Africa and instantly "felt a connection".

"We are very grateful to have him in our lives," the two said in a joint statement.

The Tomb Raider star's father, actor Jon Voight, stunned a pre-Oscar party audience by telling them he had become a grandfather.

Jolie was the number one choice to star in Tomb Raider

"I don't know much about it but I would be willing to go over and babysit," the Midnight Cowboy star told those gathered at a special lunch for Oscar nominees.

The couple only received their new son on Tuesday following extensive background checks.

They said they plan to spend the next few months in Asia and Africa, where Jolie is filming, before returning to the US.

Jolie - a United Nations goodwill ambassador - said although their baby has been given an American name he will also have a Cambodian name.

Colourful

The 26-year-old also said her son will be raised in both the US and his home country.

Jolie married Monster's Ball actor Thornton two years ago and their colourful lives have been the talk of Hollywood gossip pages.

Thornton has two children from his previous marriage.

Angelina Jolie films

Hackers (1995) Playing God (1997) Gia (1998) Pushing Tin (1999) The Bone Collector (1999) Girl, Interrupted (1999) Gone in 60 Seconds (2000) Tomb Raider (2001)

"In May, we return home where his brothers Willie and Harry are very excited to meet him," the couple said.

Prior to her official appointment as a UN ambassador, the actress had paid discreet visits to a number of countries on behalf of the UNHCR, among them Cambodia, where scenes from Tomb Raider were shot.

Also last year, she spent $500,000 (�352,000) taking a UN team to the troubled African nation Sierra Leone for 18 days.

There she met maimed and traumatised refugees who told how relatives and friends were raped and murdered during years of civil war.