All drugs including cocaine, heroin and crystal meth will be legal in Mexico within 10 years, said the country’s former president Vicente Fox, after a court ruling that he said makes the legalisation of marijuana inevitable.

“I think marijuana [legalisation] is a first step,” Fox told Reuters on Tuesday. “It’s now irreversible.”

Fox was president between 2000 and 2006 and became an advocate of legalising drugs after leaving office.

Earlier this month, the supreme court approved growing marijuana for recreational use. The landmark decision blasts open the door for an eventual legalisation in Mexico, where warring gangs have waged a decade of drug violence.

Now that the court has ruled that it is unconstitutional to prevent people from smoking marijuana, Fox said it would eventually have to make a similar decision for drugs like cocaine and heroin.

“The other drugs will take a longer cycle, say five to 10 years,” he said.

In a 2013 interview, Fox told Reuters he believed Mexico could legalize pot by the end of current president Enrique Peña Nieto’s six-year term in 2018, which had seemed far-fetched to many at the time, but now appears possible.

Peña Nieto, who has repeatedly said he is against legalisation, has called for a national policy debate on the issue of marijuana reform.

Last week, the deputy interior minister, Roberto Campa, the government official overseeing a review of marijuana policy, said questions such as easing custodial sentences and raising the amount of the drug that people can carry will be considered.

When Fox, a former Coca-Cola executive, won the presidency in 2000 as the candidate of the conservative National Action Party (Pan) it ended 71 years of uninterrupted rule by Peña Nieto’s Institutional Revolutionary Party (Pri).

Since leaving office, Fox has earned a reputation for speaking his mind and butted heads with the Pan after he voiced support for Peña Nieto in the run-up to the 2012 election, which handed the presidency to the Pri after 12 years of Pan rule.

Nonetheless, his backing of Peña Nieto and his ability to be heard by conservatives on issues they normally chafe at, such as drugs reform, mean many listen when Fox speaks.

Fox said he had no interest in commercialising marijuana himself once legalised but expected major agribusinesses to be interested.

“If they regulate freely so you can produce to export, the big guys are going to jump in,” he said, adding that Nafta-style regulations would be needed if both Mexico and the United States eventually legalise marijuana.

Possessing and consuming tiny amounts of drugs including marijuana and cocaine were decriminalised in Mexico in 2009. The US states of Colorado, Oregon, Washington, Alaska and the District of Columbia have legalised pot use.

But, it is still early days for federal legalisation in both countries, Fox said.

“Obama has to resolve his things over there and Peña Nieto has to make sure he sorts out this problem here,” Fox said. “Everything in good time.”

Fox said he approved of Peña Nieto’s strategy against the country’s drug gangs, despite this year’s high-profile jailbreak of drug kingpin Joaquín “El Chapo” Guzmán.

