The US and Europe need a new strategy on drugs and should look at alternatives such as the regulated sale of marijuana, says the Uruguayan president, José Mujica, whose country recently legalised the production and sale of cannabis.

In an interview on Thursday, the 78-year-old former leftwing guerrilla said the world's largest economies, which are the biggest markets for illegal narcotics, needed to tackle drug trafficking using tools other than prohibition.

"The industrial societies are the ones that have to change," he said. "For a small country, it's possible to experiment with this, but it's also very possible for a developed country because of the resources it has."