By Rupert Wingfield-Hayes BBC correspondent in Beijing

China and South-East Asia are being flooded by vast quantities of amphetamine-based drugs, according to officials meeting in the Chinese capital, Beijing.

Delegates from six Asian nations and the United Nations are warning that concerted efforts to reduce the production of drugs like opium and heroin are now being undermined by the huge increases in the production of artificial stimulants.

Statistics released to coincide with this meeting in Beijing show that 80% of all amphetamine seizures in the world are now made in East and South-East Asia.

Thailand is one of the biggest producers of opium

Half of all the people abusing amphetamines live in the same region.

And the spread of amphetamines is, according to drug officials, much harder to fight than traditional drugs.

They say the production of opium by poor farmers is by and large the product of poverty, but drugs like ice and Ecstasy can be produced anywhere and their production is far more the product of greed.

That is not to say that the scourge of opium and heroin has gone.

Seventy per cent of all heroin seizures in the world are still made in East and South-East Asia, and with the war in Afghanistan cutting production there, China and Burma now once again have the dubious honour of being part of the biggest opium-producing region in the world.