Carl's Jr will be the first fast food chain to sell a CBD-filled hamburger when its Rocky Mountain High Cheeseburger Delight goes on sale in Denver on Saturday, April 20.

The burger for sale has “Santa Fe Sauce” seasoned with cannabis CBD oil, a non-psychoactive component of cannabis that can help calm and relax, but doesn't uplift.

“CBD is one of the hottest culinary trends right now, and what could be better for testing this new burger than Denver, the city that was a pioneer in the CBD movement,” said Candice Jacobson, spokeswoman for Carl Jr.

Recreational, i.e. occasional irregular or occasional use of cannabis was legalized in Colorado in 2014. CBD Burger Oil is supplied by the local Bluebird Botanicals.

A spokeswoman for Carl Jr added that Carl's Jr chain, owned by CKE Restaurants Holding Inc, a private company, could expand burger sales as the rules allow.

Jack burger - such a slang term for smoking cannabis - with pickled jalapenos and peppers will cost $ 4.20 - the number marking the annual date for cannabis celebration in the United States is April 20.