The UN AIDS envoy for eastern Europe on Thursday said Crimea faced a "human tragedy" and risks to public health after a programme for intravenous drug users was scrapped following Russia's takeover.

"Politics has won out over science -- and doctors, scientists, and humanitarians are right to feel abhorrence that a new human tragedy has been imposed on Crimea," Michel Kazatchkine said in a commentary published by the British Medical Journal (BMJ).

Kazatchkine said that under Ukrainian rule, Crimea provided addicts with access to methadone, a safer substitute for heroin, and to buprenorphine, a drug used to ease dependence.

Endorsed by the World Health Organisation (WHO), this "substitution" therapy is a proven success in weaning addicts off heroin and halting the spread of HIV, Kazatchkine said.

But under Russian law, these drugs are prohibited, and leading figures in Russian law enforcement and addiction treatment, as well as the peninsula's deputy prime minister and deputy health minister, all oppose them, he said.

"This will bring unnecessary suffering to the people of Crimea and is a blatant example of health policy being hijacked for political ends rather than being led by evidence," he charged.

Dosages of drugs for the 800 people enrolled in Crimea's substitution programme were gradually reduced from mid-March and the therapy officially stopped on May 1, Kazatchkine said.

About 80 people have sought to leave Crimea to continue treatment, 32 of whom are also receiving AIDS drugs, he said, quoting the International HIV/AIDS Alliance in Ukraine.

Under Ukraine's governance, Crimea also widely used needle exchange programmes and focussed support on sex workers and gays, which are also important niche groups for the spread of HIV. The services cover 14,000 people, Kazatchkine said.

"Many of these services are limited, however, if available at all in Russia," said Kazatchkine.

Kazatchkine, a former chief of the Global Fund to Fight AIDS, Tuberculosis and Malaria, published his comments ahead of a conference in Moscow on the HIV/AIDS epidemic in eastern Europe and central Asia next Monday and Tuesday.

Russia has one of the fast-growing tallies for HIV infections in the world. Experts say the spread is being driven by intravenous drug use, but is now entering the mainstream community.

According to UNAIDS, the Russian Federation had 170,000 people who were infected with the human immunodeficiency virus (HIV) in 2004, a figure that rose to 1.2 million last year.

Russia accounts for over 55 percent of all new HIV infections reported in the European region, according to the European Centre for Disease Prevention and Control (ECDC).