Bill Gates has admitted a new type of synthetic butter he is backing is "strange" amid a spiralling backlash against the synthetic product.

Savor, billed as an eco-friendly identical substitute to butter, was launched in March this year - with Gates writing of how it could be an "immense" opportunity to reduce our carbon footprint.

But a backlash to the foodstuff has erupted after a CBS News feature on the fake butter went viral online.

Celebrity chef Andrew Gruel blasted: "Disgusting. They are combining hydrogen, carbon and oxygen to create fat molecules then manipulate that to taste like butter.

"Why do this when we already have butter?"

A backlash to the foodstuff (pictured) has erupted after a CBS News feature on the fake butter went viral online

Gruel has also urged US Health Secretary Robert F Kennedy Jr to step in and ban the product in the States.

"Secretary Robert F Kennedy Jr, [Agriculture] Secretary [Brooke] Rollins, you should not allow this to be marketed or labelled as butter, nor should any government agencies contract to serve this to people," he added.

Bill Gates himself has said: "The idea of switching to lab-made fats and oils may seem strange at first. But their potential to significantly reduce our carbon footprint is immense."

One of Savor's food scientists, Jordan Beiden-Charles, has hailed how the product is made "with no agriculture whatsoever".

"This is pretty novel, to be able to make food that looks and tastes and feels exactly like dairy butter, but with no agriculture whatsoever... And without a long ingredient list the average person can't pronounce," he said.

"It's really just our fat, some water, a little bit of lecithin as an emulsifier, and some natural flavour and colour."

Bill Gates has admitted a new type of synthetic butter he is backing is 'strange'

The firm has also detailed just how the phony butter is made.

Savor says it harvests carbon dioxide from the air and hydrogen from water, heats them up, then oxidises them.

That makes a final result which resembles candle wax, but is actually fat molecules like those in beef, cheese or vegetable oils.

CEO Kathleen Alexander said: "You're using this gas right now to cook your food - and we're proposing that we would like to first make your food with that gas."

She added that the butter is set to hit shelves by 2027.

RFK Jr has been told to step in

But lab-grown food has already sparked concern around the world - both Italy and the state of Florida have banned artificial meat over concerns the industry threatens traditional farming.

The Royal Agricultural University then commissioned a study last summer which labelled synthetic products a "slow-burn risk" to farms in the long-term.

However, Professor Tom MacMillan, who led the research, said: "Sure, there was a deal of concern about how it might play out, the unintended consequences for farming.

"But there was a lot of curiosity to something often seen as the enemy."