Billionaire activist investor Carl Icahn has said he is close to launching a proxy contest at McDonald’s, disgruntled with the burger chain’s treatment of pigs.

Unhappy that McDonald’s sources pork from suppliers that house pregnant pigs in small crates, Icahn told Bloomberg that he is “probably 90%” from putting up a slate in a bid to fight the practice, which the activist sees as inhumane.

“We’re not going to fool around with them anymore,” said Icahn, who only holds 100 shares in the fast-food chain.

The activist said he was still discussing with McDonald’s to end the use of gestation crates, adding that he would not hesitate to nominate a “few people” to the restaurant company’s board if things do not change.

Icahn said he was particularly disappointed with the company’s top echelon for not living up to a promise made a decade ago to no longer deal with suppliers using sow gestation stalls, which are too small in length and width for pigs to move about or even lie down.

“That’s a situation that is just horrible. It’s obscene. You got these companies making all this money and the animals are just suffering for no reason,” said Icahn, whose net worth is estimated at about $24 billion.

Since 2018, shareholder proposals on animal welfare have received on average less than 10% support according to Proxy Insight Online data, peaking at an average of 7.4% support in 2021.

For example, a May 2020 proposal from Harrington Investments that pushed for Kohl’s to reduce animal cruelty in its supply chain received just 5.1% support. Similarly, a June 2021 proposal that urged TJX Companies to report on animal welfare received just 9.3% support.

Shares in McDonald’s are up 17% over the last 12 months while the burger chain’s market cap stands at $190 billion. The company has 12 board members and typically holds its director elections in May.