The governor of one of Mexico's most violent states is making waves by proposing that impoverished farmers be allowed to grow opium poppies for legal medical use.

Guerrero state is among Mexico's poorest, and many remote mountain communities already grow small plots of poppies, which are bought by drug cartels that have fought violent turf battles throughout the Pacific coast state.

It has become the biggest opium-producing state in Mexico, supplying about half the heroin used in the United States.

Guerrero Gov. Hector Astudillo suggested this week that farmers be allowed to produce opium for legal medical use.

Astudillo, a member of President Enrique Pena Nieto's Institutional Revolutionary Party, later said his comments were more thinking-out-loud than a concrete proposal.

But they illustrate the government's difficulty in weaning small farmers away from what is often their only alternative to migration. Local farmers often raise corn on their dry mountain plots, but don't grow enough to even meet their own needs. Many keep an acre or so of irrigated poppies to provide an income.

Some say that if more farmers worked for the legal market, it could undermine the power of drug cartels that are now their only buyers.

Lisa Sanchez, who oversees drug policy for the NGO Mexico United Against Crime, is among those who find the proposal interesting.

"The debate has to be oriented toward legal routes for growing poppies, because any orderly market would take power away from the cartels and reduce the violence, even though that is not a magic solution, nor the only one," Sanchez said.

But others say the proposal may be a nonstarter in a world where demand for legal opiates is already being met. They say the kind of controls needed for legal production can't be implemented in the remote, cartel-dominated mountains.

No 'sufficient demand'

Antonio Mazzitelli, the representative in Mexico for the UN Office on Drugs and Crime said the proposal "is not at all viable."

"There isn't sufficient demand to justify more production," Mazzitelli said.

Instead, he said, Mexico should focus on "long-term development alternatives" such as roads, infrastructure and crop substitution that would permit farmers to grow non-drug crops.

The global legal market for opiates is overseen by the International Narcotics Control Board, an arm of the United Nations.

The board calculates demand based on each country's needs and organizes supply in a handful of nations — Australia, France, Hungary, India, Spain and Turkey are some of the largest — that must comply with security and quality requirements to be approved as producers. It also registers all legal global production and oversees transactions to avoid diversions into the black market.

Mazzitelli said Mexico would have difficulty meeting those requirements and in any case, legal poppies could not be cultivated where the plant is grown now because of the difficulties, danger and cost involved in trying to monitor the crop in remote mountainous areas where the state has little effective control.