Nebraska and Colorado might share a border, but they are not on good terms.

The two US states have locked horns over Colorado’s liberal marijuana rules.

(Nebraska is one of the country’s three conservative states that ban marijuana in all shapes and forms.)

Now, they’re at war over meat.

Colorado Governor Jared Polis last month declared March 20 to be ‘MeatOUT Day’; a bid to reduce meat consumption in the name of health, animal welfare and the environment.

Nebraska is not on board with the concept.

The state’s Governor Pete Ricketts said it was a “direct attack on our way of life”.

Ricketts made the proclamation from a butcher shop in Omaha, the state’s biggest meat-consumption city, to amplify his point.

In retaliation, he declared March 20 in Nebraska to be ‘Meat on the Menu Day’.

Beef is the biggest industry in Nebraska – it even calls itself the Beef State on car licence plates.

Beef – it’s what’s for breakfast, lunch and dinner in Nebraska.

“If you were to get rid of beef in our country, you would be undermining our food security, an important part of a healthy diet, and also destroying an industry here in our state that’s very important,” Ricketts said.

Polis’ meat-free movement has disgruntled some of his own constituents – beef farming is still big business in Colorado.

Weld County, the leading county for the beef industry in Colorado, has signed off to make March 20 ‘Meat-IN Day’, and 26 other countys have flocked to the cause.

“We are supporting a ‘Meat In’ movement instead … meet in a restaurant and order your favourite meat dish, meet your family and friends for a meal featuring meat,” the Colorado Cattlemen’s Association said.

“Let’s focus on keeping meat in and on the breakfast, lunch, and dinner table.”

The next state election for Colorado is in June next year.