Gil Kerlikowske, the U.S. president's director of national drug control policy, said the United States is taking a more balanced approach to substance abusers rather than fighting a "war on drugs" centered mainly on law enforcement.

Speaking to reporters during a visit to London, Kerlikowske, a former police chief, said major advances in medical science had shown that drug abuse disorders are chronic diseases of the brain that can be effectively prevented and treated.

He said the international community should recognize this and work together on program to prevent and treat abusers, help addicts recover, and explore reforms to criminal justice systems to stop the revolving door of drug use, criminal behavior, jail, release, and re-arrest.

"It's very clear we can't arrest our way out of this problem," he said. "The availability of quality treatment and the engagement of the public health sector and primary care physicians in drug issues is very critical."

While officials say overall illicit drug use in the United States has dropped substantially over the past 30 years, there are upwards of 20 million Americans who could benefit from treatment and recovery programs, Kerlikowske said. Currently, only around 4 million of these get the kind of help they need.

Prescription drug abuse has become a serious concern in the United States in recent years and was the second-biggest factor behind accidental deaths in 2007.

Kerlikowske, who was in London as part of a tour through Sweden, Britain and Russia this week, said the Obama administration was eager to talk to those dealing with drug addiction problems in other countries to see whether elements of their approaches could be useful in the United States.

He has also previously visited Portugal and Italy, as well as Mexico, Colombia and other countries in South America to see different kinds drug treatment programs and prevention plans.

He noted what he described as a "somewhat successful" fresh approach in Portugal, where since 2001 authorities have dispensed with arrests, trials and prison for people carrying a personal supply of any drug from marijuana to heroin and focused their efforts on prevention messages and treatment.

"We're happy to learn from and visit and have our eyes wide open to look at these other countries," he said. "But it should be noted that about 85 percent of all drug treatment research is conducted or funded in the United States...so we're also happy to share with other countries what we have learned."

Drug enforcement experts in the United States say the evidence strongly supports the wider use of drug courts, which seek to impose treatment programs instead of prison sentences on repeat criminals who are dependent on illegal drugs.

Kerlikowske said he had never been a fan of the concept of a "war on drugs". However, just a few years ago, he said he would have agreed with what he says was probably the majority view among the American public -- that if you had a drug problem "you just needed to find God or pull yourself up by your bootstraps."

Now scientific research has changed that view, he said. "The scientists..have all recognized addiction as a disease, and it doesn't take a huge amount of reading of research papers to understand and accept the scientific evidence.

"The problem is that is disease is chronic. Unfortunately, it doesn't led itself to a quick fix."

(Reporting by Kate Kelland, editing by Rosalind Russell)

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