Anne - 'It is extremely depressing'

The news came as Princess Anne travelled to the capital Phnom Penh as part of a campaign to free children from the grip of sex tourism.

She was told Cambodia has the worst HIV problem in Asia and its children are increasingly at risk.

Secret filming by the BBC last year showed that children of primary school age are regularly sold for sex - and many of their clients are British men.

But in an effort to teach children to protect themselves a new project has been launched by Buddhist monks - backed by the government, keen to water down the negative image of their country.

The monks are using their trusted place in the Cambodian community to educate children about sex tourism and how they can avoid getting caught in the trap.

Cambodian officials are uncomfortable with Glitter's conviction

It is this project that Princess Anne - president of Save The Children for more than 30 years - was visiting and she gave it her full support.

She told the BBC: "An enormous group of children are particularly vulnerable to what is seen by everybody as the easiest way of exploiting children - through sex.

"I think all of us would find it extremely depressing that tourism - that seems like such a good idea and which brings economic relief to a country like this - is actually bringing with it a very very dark side of tourism, bringing sex exploitation."

The government is sensitive to the charge that Cambodia is a free country for those wanting to exploit the sex trade, particularly against children.

When it emerged Glitter was living in the capital an investigation was immediately launched.

Police seized his passport on Sunday after he was detained for questioning and later released.

But they now say they cannot expel him as he has not actually committed a crime in Cambodia.