* "War on drugs" no longer defines U.S. policy - Kerlikowske
* Legalisation also won't end international drug crime
* "Third way" focuses on prevention and treatment
By Fredrik Dahl
VIENNA, June 26 (Reuters) - Legalising drugs was no "silver bullet" that would make organised crime disappear, President Barack Obama's drugs policy chief said on Wednesday, as Latin American countries explore relaxing penalties for the personal use of narcotics.
Gil Kerlikowske, a former police chief, told an international meeting in Vienna that arresting more users and building prisons to put them in was also not the answer to the drug problem in the United States.
Instead, this year's U.S. National Drug Control Strategy presented a "third way ... rooted in a science-based approach to drug addiction as a disease of the brain that can be prevented, treated and from which people can recover."
Kerlikowske said he had banished the phrase "war on drugs" after taking office four years ago, and the U.S. federal government now spent more on drug prevention and treatment than domestic law enforcement.
But "the end of the 'war on drugs' does not mean we are giving up on our efforts or making dangerous, addictive drugs more easily available for abuse," Kerlikowske added.
RETHINK IN LATIN AMERICA
Countries in Latin America, the world's top producer of cocaine and marijuana, have begun openly to challenge the 40-year orthodoxy of a U.S.-led "war on drugs" that sought to stamp out the cultivation and distribution of drugs.
Frustrated by ceaseless bloodshed and a perception that the United States had not done enough to curb its own drug consumption, many leaders in the region have debated the possibility of legalizing drugs.
In Mexico, more than 70,000 people have been killed in drug-related violence since former President Felipe Calderon launched a military-led campaign against the drug gangs in 2006.
Ten years ago, the United States might have reacted with alarm to any shift in Latin American drug policies, but Obama's administration has refrained from openly criticising changes in drug laws partly because U.S. attitudes are also in flux.
But Kerlikowske, Obama's director of national drug control policy, did warn against expecting a quick fix by legalising drugs. Earlier this month, Vermont became the 17th U.S. state to decriminalize possession of small amounts of marijuana.
He said legalisation was not a "silver bullet that would magically cause transnational organised crime to disappear ... that is a fallacy and a distraction from global efforts to disrupt and dismantle" such criminal gangs.
The United States is "engaged in confronting violent transnational criminal organisations across the globe," he said.
Kerlikowske was speaking after the U.N. Office on Drugs and Crime, in an annual report published on Wednesday, said use of heroin and cocaine seemed to be declining in some parts of the world.
But the UNODC's 2013 World Drug Report also showed that abuse of prescription drugs and new psychoactive substances - marketed as "designer drugs" and "legal highs" - was increasing.
Use of new psychoactive substances - with names that entice young people into thinking they pose no risk - among youth in the United States appears to be more than twice as widespread as in the 27-nation European Union, the report said.
But cocaine consumption has plunged in the United States - the world's largest market for the drug. UNODC said it fell by 40 percent between 2006 and 2011, partly linked to less production in Colombia and violence between drug cartels. (Editing by Mike Collett-White)