UK pharmaceutical giant GSK says it will pay as much as $2.2bn (£1.68bn) to settle thousands of cases in US courts over claims that a discontinued version of its heartburn drug Zantac caused cancer.

The firm announced that it had reached agreements with 10 law firms who represent around 80,000 claimants. The settlements account for 93% of all cases.

GSK will also pay $70m to resolve a whistleblower complaint by a laboratory that alleged the drugmaker defrauded the US government by concealing Zantac’s cancer risks.