The Trump administration has told companies not to warn customers about products that contain glyphosate, a decision targeted at a California regulation that requires labels to warn consumers that the Roundup ingredient is potentially cancer-causing.

The U.S. Environmental Protection Agency says it will no longer approve labels warning glyphosate is known to cause cancer. The chemical, marketed as a weed killer by Monsanto under the brand Roundup, is currently the focus of lawsuits from thousands of consumers alleging it caused their cancers.

Such labels are "irresponsible," EPA Administrator Andrew Wheeler said in a statement. He cited the EPA's conclusions that the chemical doesn't represent a cancer risk.

Get Breaking News Delivered to Your Inbox Click here to view related media. click to expand

The decision from the EPA highlights the growing debate over the safety of glyphosate, with scientific research often reaching contradictory conclusions. The World Health Organization's cancer agency has said that the chemical is "possibly carcinogenic to humans," yet on the other side of the debate are studies that refute reports of glyphosate's risks, such as a long-term study of agricultural workers that didn't find a link between Roundup and cancer.

What you need to know about glyphosate

Since Bayer bought Roundup maker Monsanto in June 2018, the company has lost lost three high-profile court cases that alleged the chemical caused cancer.

"It is critical that federal regulatory agencies like EPA relay to consumers accurate, scientific based information about risks that pesticides may pose to them," Wheeler said in the statement. "EPA's notification to glyphosate registrants is an important step to ensuring the information shared with the public on a federal pesticide label is correct and not misleading."

California's law

California requires warning labels on glyphosate products because the International Agency for Research on Cancer has said it is "probably carcinogenic."

Monsanto has sued to block California's warning label requirements. A federal judge blocked California from enforcing the labels while the lawsuit continues.