Bayer has agreed to pay over US$10 billion to settle thousands of claims that its popular weedkiller Roundup causes cancer, the company announced on Wednesday.

The world’s largest seed and pesticide maker will make a total payment of US$10.1bn  - US$10.9bn "to resolve current and address potential future Roundup litigation", it said.

Bayer says the resolution will bring closure to approximately 75% of the current Roundup litigation in the U.S. involving approximately 125,000 filed and unfiled claims that the product causes non-Hodgkin’s lymphoma.

The cases were brought against Bayer's U.S.-based subsidiary Monsanto, which it acquired in 2018.

The resolved claims include all plaintiff law firms leading the Roundup federal multi-district litigation (MDL) or the California bellwether cases, and those representing approximately 95% of the cases currently set for trial, and establish key values and parameters to guide the resolution of the remainder of the claims as negotiations advance, Bayer said.

The resolution also puts in place "a mechanism to resolve potential future claims efficiently", it added.

Up to US$9.6bn of the payment will be to resolve current Roundup litigation, while US$1.25bn will support a separate class agreement to address potential future litigation.

The resolutions were approved unanimously by Bayer’s Board of Management and Supervisory Board with input from its Special Litigation Committee. The agreements contain no admission of liability or wrongdoing.

“First and foremost, the Roundup settlement is the right action at the right time for Bayer to bring a long period of uncertainty to an end,” said Werner Baumann, CEO of Bayer.

“It resolves most current claims and puts in place a clear mechanism to manage risks of potential future litigation. It is financially reasonable when viewed against the significant financial risks of continued, multi-year litigation and the related impacts to our reputation and to our business."

The New York Times reported that most of the lawsuits filed early on were brought by homeowners and groundskeepers, although they account for only a tiny portion of Roundup’s sales.

Farmers are the biggest customers, and many agricultural associations contend glyphosate, the key ingredient in Roundup, is safe and effective, the publication reported.

“It’s rare that we see a consensual settlement with that many zeros on it,” Nora Freeman Engstrom, a professor at Stanford University Law School, told the New York Times.