Health and Human Services Secretary Robert F. Kennedy Jr. told top food executives on Monday that he wants “the worst ingredients” out of food and is willing to take action to get rid of them.

Removing artificial dyes from the food system is an urgent priority of the Trump administration, and Kennedy said he wants to do so by the end of his time in office, according to a memo summarizing the meeting sent by the Consumer Brands Association that was viewed by CNBC. While Kennedy said he wanted to work with the food industry, he also “made clear” that he would take action if the industry wasn’t proactive.

“It was a constructive conversation and we look forward to continued engagement with the secretary and the qualified experts within HHS to support public health, build consumer trust and promote consumer choice,” Consumer Brands Association CEO Melissa Hockstad said in a statement to CNBC.

Meeting attendees included the CEOs of PepsiCo North America, Kraft Heinz, General Mills, Tyson Foods, WK Kellogg, J.M. Smucker and the Consumer Brands Association, the industry’s top trade group.

“We appreciate the Secretary taking the time to sit down with us and view the meeting as a productive first step in working with the Administration,” a PepsiCo spokesperson said in a statement to CNBC.

Bloomberg first reported details of the meeting.

Kennedy is at the helm of a $1.7 trillion agency that oversees food and tobacco products, vaccines and other medicines, scientific research, public health infrastructure and government-funded health care.

His so-called Make America Healthy Again platform argues a corrupt alliance of drug and food companies and the federal health agencies that regulate them are making Americans less healthy. He has pledged to end the chronic disease epidemic in children and adults, and has been vocal about making nutritious food, rather than drugs, central to that goal.

In January, before President Donald Trump or Kennedy took office, the Food and Drug Administration revoked its authorization of one type of red food dye called Red No. 3. The dye is known to cause cancer in laboratory animals, but was allowed to be used by food manufacturers for years because scientists didn’t believe it raised the risk of cancer in humans at the level it is typically consumed.

Kennedy, a notorious vaccine skeptic, is also making early moves that could impact immunization policy and further dampen uptake in the U.S. at a time when childhood vaccination rates are falling. He has said he will review the childhood vaccination schedule, and is reportedly preparing to remove and replace members of external committees that advise the government on vaccine approvals and other key public health decisions, among other efforts.