BERLIN, March 22 (Reuters) - Bayer was ordered by a jury in the U.S. state of Georgia to pay about $2.1 billion to a plaintiff who claimed the company's Roundup weed killer caused his cancer, the plaintiff's law firms said late on Friday.

The verdict, which Bayer said on Saturday it would appeal, is one of the largest legal settlements issued in a Roundup-related case and is the latest setback for the group, among the world's largest seeds and pesticides makers.

Bayer has paid about $10 billion to settle disputed claims that Roundup, based on the herbicide glyphosate, causes cancer. Over 60,000 further cases are pending for which the group has set aside $5.9 billion in legal provisions.

The Georgia verdict includes $65 million in compensatory damages and $2 billion in punitive damages, according to a statement emailed to Reuters by the plaintiff's law firms Arnold & Itkin LLP and Kline & Specter PC.

Bayer said in a statement it disagreed with the jury's verdict, as it conflicted with the overwhelming weight of scientific evidence and the consensus of regulatory bodies and their scientific assessments worldwide.

"We believe that we have strong arguments on appeal to get this verdict overturned and the excessive and unconstitutional damage awards eliminated or reduced," it said.

Earlier this month, Bayer told U.S. lawmakers it could stop selling Roundup unless they strengthened legal protection against product liability litigation, a financial analyst and person close to the matter told Reuters.

(Reporting by Riham Alkousaa; Editing by Emelia Sithole-Matarise)