Mexico's president, Felipe Calderón, has joined calls for a debate on the legalisation of drugs as new figures show thousands of Mexicans every year being slaughtered in cartel wars. "It is a fundamental debate," the president said, belying his traditional reluctance to accept any questioning of the military-focused offensive against the country's drug cartels. "You have to analyse carefully the pros and cons and key arguments on both sides." The president said he personally opposes the idea of legalisation.