Ben & Jerry’s will be destroyed as a brand if it remains with parent company Magnum, the company’s co-founder Ben Cohen has told the BBC.

His remarks are the latest in a long-running spat between the ice cream brand and its parent company over its ability to express its social activism and the continued independence of its board.

On Monday the Magnum Ice Cream Company (TMICC) started trading on the European stock market – spinning off from owner Unilever.

A spokesperson for Magnum said the firm wanted to build and strengthen Ben & Jerry’s “powerful, non-partisan values-based position in the world”.

Ben & Jerry’s was sold to Unilever in 2000 in a deal which allowed it to retain an independent board and the right to make decisions about its social mission.

Since the sale there have been deepening clashes between the Vermont-based brand and Unilever, with this conflict now inherited by Magnum.

In 2021, Ben & Jerry’s refused to sell its products in areas occupied by Israel, resulting in its Israeli operation being sold by Unilever to a local licensee, and in October, Ben Cohen said it was prevented from launching an ice cream which expressed “solidarity with Palestine”.

Last month, ahead of its spin off from Unilever, Magnum said the chair of Ben & Jerry’s board Anuradha Mittal, who has held the position since 2018, “no longer meets the criteria to serve” – saying this was the result of an internal audit.

A spokesperson for Magnum said it had found “a series of material deficiencies in financial controls, governance and other compliance policies, including conflicts of interest”.

“So far, the trustees have not fully addressed the deficiencies identified,” they said.

In a statement to Reuters, Ms Mittal said: “The so-called audit of the foundation was a manufactured inquiry – engineered to attempt to discredit me.

“It is important to understand that this is not simply an attack on me as chair. It is Unilever’s attempt to undermine the authority of the Board itself.”

The BBC has contacted Ben & Jerry’s to request this statement.

Mr Cohen said Magnum “has no standing to determine who the chair of the independent board should be”.

“Therefore, by trying to [change the chair of the board], I would say that Magnum is not fit to own Ben & Jerry’s,” he added.

Mr Cohen called for either the business to be “owned by a group of investors that support the brand and want to encourage the values” or for Magnum to make a “180 degree turn around and say they support the chairman of the independent board”.

Ahead of the spin off on Monday, news agency Reuters reported that Ms Mittal said she had no plans to step down from the board.

Ben Cohen remains an employee of Ben & Jerry’s and the brand’s most high-profile spokesperson.

He told the BBC he feared under the current ownership the ice cream maker’s “loyal” followers would be lost for good.

“If the company continues to be owned by Magnum, not only will the values be lost, but the essence of the brand will be lost,” he said.

On Sunday, Magnum’s chief executive Peter ter Kulve told the Financial Times the Ben & Jerry’s founders were in their seventies and “at a certain moment they need to hand over to a new generation”.

Jerry Greenfield, Mr Cohen’s co-founder, left the ice cream maker in September after almost half a century at the firm – citing concerns about the stifling of its social mission.

“It’s absurd,” said Mr Cohen.

“This is about values and abiding by a legally binding agreement.”

Mr Cohen added investors in Magnum were being asked to pay a premium for the Ben & Jerry’s brand “because it has such a loyal following”.

“As they destroy Ben and Jerry’s values, they will destroy that following and they will destroy that brand,” he said.

“It’ll become just another piece of frozen mush that just going to lose a lot of market share.”

A spokesperson for Magnum said Ben & Jerry’s was “not for sale” and it had “always respected” the brand’s commitment to continue its “social mission”.

The demerger of Unilever’s ice cream business saw primary shares in Magnum open at €12.20 (£10.66) – down on the expected €12.80 (£11.18) reference price set by the EuroNext exchange in Amsterdam. But it bounced back up by 1.3% at close of trading.

The spin off means Magnum is now the world’s biggest standalone ice cream business.