BANGKOK, August 20, 2008 (AFP) - Thailand declared British former glam rocker Gary Glitter 'persona non grata' Wednesday and moved to deport him to Britain, one day after he finished prison time in Vietnam for child sex offences.

The order was set to end Glitter's state of limbo since he arrived overnight at Bangkok airport from Vietnam, where he had spent almost three years behind bars for committing obscene acts with two girls aged 11 and 12.

The 64-year-old singer had been due to board a connecting flight to London but instead stayed in the airport complaining of chest pains.

A doctor pronounced him fit to fly, saying he was suffering only a minor inflammation in his chest, a medical official at the airport told AFP.

Glitter -- real name Paul Francis Gadd -- then refused to board the next flight to London, but Thailand's immigration chief said later Wednesday he had been declared persona non grata and would be expelled to Britain.

'Paul Francis Gadd will be deported to his home country, England, unconditionally and as soon as possible,' Lieutenant General Chatchawal Suksomjit said in a statement.

'He poses a danger to a peaceful and orderly society and offends Thai morals,' Chatchawal added.

'He is on our watch list as persona non grata. Thai immigration cannot let him enter,' Chatchawal told AFP earlier.

Glitter arrived here from Vietnam late Tuesday after spending two years and nine months in jail for committing obscene acts with the two girls in the southern resort town of Vung Tau in 2005.

The British embassy in Bangkok said they had offered him consular help but that his fate was up to Thailand.

Britain has not announced any outstanding charges against the singer once famed for his flamboyant bouffant wigs and silver jumpsuits, but British Home Secretary Jacqui Smith said he should not be allowed to leave once he returns.

'We need to control him, and he will be, once he returns to this country,' Smith told talkSPORT radio.

She said Glitter would have to sign a sex offenders' register and notify authorities if he wants to travel abroad.

'It certainly would be my view that with the sort of record that he's got, he shouldn't be travelling anywhere in the world,' she added.

Glitter had several hits in the 1970s including 'I'm The Leader Of The Gang (I Am!)' and 'Do You Wanna Touch Me?' The anthemic 1972 hit 'Rock and Roll' is still often chanted in British and US sports stadiums.

He was arrested in Britain in 1997 after he took his computer to a repair shop, where hardcore child pornographic material was found on its hard drive.

He was sentenced in 1999 to four months in prison, of which he served two.

Keen to avoid the media, Glitter reportedly moved to Cuba and then Cambodia, where he was expelled in 2002, allegedly for trawling for underage sex.

Having settled in communist Vietnam, where a British newspaper reported he was living with an underage girl, he was arrested at Ho Chi Minh City airport in November 2005 while trying to leave for Thailand.

In March 2006 he was sentenced to three years in prison, the minimum term under Vietnamese law, which was later cut by three months.

The singer maintained his innocence, blamed a media conspiracy and claimed he was teaching the girls English and allowed them to stay overnight because they were scared of ghosts.

Child protection workers called for his deportation back to Britain.

'We don't feel it's appropriate he spends his time hopping from one country to the next one while countries decide what to do with him,' said Mark Capaldi, deputy director of Ecpat International, a child protection charity.