Virgin Group founder and billionaire Sir Richard Branson thinks that instead of raising cows, farmers in New Zealand should grow cannabis, he said in a recent interview with Newshub.

During a visit to the country to speak at a charity fundraiser, Branson said he predicts that within the next 10 years, marijuana use will be just as acceptable as drinking wine, he told Newshub. In New Zealand, it is currently illegal to grow, possess or use cannabis.

During the interview, Branson said that the war on drugs has failed and that legalization of marijuana would be an economic benefit.

"We've done a lot of studies on the war on drugs, and it's been an abject failure," Branson told Newshub. "What is absolutely clear to us is that drugs should be decriminalized, and people who have drug problems should be helped."

Branson said that legalizing marijuana would be economically advantageous, both for the farmers to grow it and for the government to tax and regulate it. [25 Odd Facts About Marijuana]

Dairy farming is the main agricultural industry in New Zealand, with more than 5 million dairy cows being milked the country, according to DairyNZ, an organization of New Zealand dairy farmers. In 2015, about 6,950 square miles (18,000 square kilometers) were used for dairy farming, according to DairyNZ.

Branson suggested that rather than expanding current dairy operations, New Zealand should look to cannabis farming as an alternative, saying that it would have a smaller environmental impact.

"I think that would be wonderful, because obviously, the amount of dairy cows that New Zealand has is damaging the rivers; if you could put some of that land over into growing cannabis, [it] would be just as profitable for them, if not more profitable," Branson told Newshub. 

Although cows used for beef are often cited as a major drain on environmental resources, dairy cows also damage the environment. According to the EPA, the runoff from cow excrements can affect the ecological health of rivers and other freshwater.

Cows are also a major source of methane, a greenhouse gas that traps infrared radiation, which contributes to global warming.

Newshub asked William Rolleston, national president of New Zealand farmer advocacy group Federated Farmers, if farmers would act on Branson's idea to choose cannabis over cows.

"Farmers welcome any opportunity to add another string to their bow, and would look at that option only if it was legal and profitable to do so," Rolleston told Newshub. "But that is a long way down the track."