Warren Buffett, the billionaire head of Berkshire Hathaway, said it would be “ridiculous” for the conglomerate not to do business with gun makers. He said he doesn’t want to impose his political views on Berkshire’s investment decisions or business operations.

Owning stock in gun makers is again controversial after the Feb. 14 mass shooting at a Florida school that left 17 students and teachers dead. Asset managers like State Street and BlackRock are weighing ownership of publicly traded weapons makers like American Outdoor Brands and Sturm Ruger and how they support the safe and responsible use of their products.

Students from the Marjory Stoneman Douglas High School in Parkland, Florida, that were targeted for mass murder by a former classmate are helping to organize the March For Our Lives, an anti-gun rally scheduled for March 24 in Washington.

Berkshire doesn’t own any gun manufacturers, Buffett said on CNBC, but there isn't any rule against it.

“I think what the kids are doing is very admirable, but I don’t think Berkshire should say we’re not going to do business with people who own guns,” Buffett said. “I think that would be ridiculous.”

The National Rifle Association on Saturday ripped into companies distancing themselves from the NRA, accusing them of “a shameful display of political and civic cowardice,” according to a report in The Washington Post.

"Let it be absolutely clear,” the NRA’s statement said. “The loss of a discount will neither scare nor distract one single NRA member from our mission to stand and defend the individual freedoms that have always made America the greatest nation in the world.”

Delta and United Airlines on Saturday joined the growing list of companies boycotting the NRA after it came under fire for its political influence following the mass shooting.

Delta tweeted it was "reaching out to the NRA to let them know we will be ending their contract for discounted rates through our group travel program,” and requested that the NRA “remove our information from their website."

United followed suit, tweeting in a similar message that it was "notifying the NRA that we will no longer offer a discounted rate to their annual meeting and we are asking that the NRA remove our information from their website."

The NRA also slammed the "failure of that school’s security preparedness, the failure of America’s mental health system, the failure of the National Instant Check System" and "the cruel failures of both federal and local law enforcement."

"Despite that, some corporations have decided to punish NRA membership in a shameful display of political and civic cowardice. In time, these brands will be replaced by others who recognize that patriotism and determined commitment to Constitutional freedoms are characteristics of a marketplace they very much want to serve," it continued.

"Let it be absolutely clear. The loss of a discount will neither scare nor distract one single NRA member from our mission to stand and defend the individual freedoms that have always made America the greatest nation in the world."

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