On Nov. 6, Americans in Colorado and Washington legalized marijuana.

Now, according to a Washington Post report, Mexico's government is "scrambling to reformulate their anti-drug strategies in light of what one senior aide said was a referendum that 'changes the rules of the game'."

As Mexico's war on drugs continues, billions of dollars have been spent trying to control the situation and around 60,000 people have been killed in drug-related violence.

"The legalization of marijuana forces us to think very hard about our strategy to combat criminal organizations, mainly because the largest consumer in the world has liberalized its laws," said Manlio Fabio Beltrones, leader of Peña Nieto's party in Mexico's Congress.

It is now legal to possess, use, display, purchase and transport marijuana accessories or one once or less of marijuana. Colorado residents can now grow up to six marijuana plants per person and consume marijuana freely. Cannabis can be legally sold and taxed at state-licensed stores.

The U.S. Department of Justice said they are reviewing the ballot initiatives.

According to a report, the new law will take effect on Dec. 6, or upon certification of the vote by Gov. Hickenlooper, whichever comes first.

"There is a sense of frustration throughout Latin America about the steep costs of confronting drug trafficking," Eric Olson, associate director of the Mexico Institute at the Wilson Center in Washington, told the Washington Post. "And these votes in the United States, and the reaction to them, might signal a willingness for the countries to think outside of the box on drug policy."