The US state of Massachusetts on Thursday filed a lawsuit accusing oil giant ExxonMobil of misleading investors on the impacts of climate change, following similar litigation in New York.

"Exxon has known for decades about the catastrophic climate impacts of burning fossil fuels -- its chief product," Massachusetts Attorney General Maura Healey said in a statement detailing the lawsuit filed in a Boston court.

"Yet, to this day, Exxon continues to deceive Massachusetts consumers and investors about the dangerous climate harms caused by its oil and gasoline products... We are suing to stop this illegal deception and penalize the company for its misconduct."

The lawsuit accuses Exxon of making "significant factual misstatements" that would have "been material to decisions by Massachusetts investors to purchase, sell, retain, and price ExxonMobil securities and by Massachusetts consumers to purchase ExxonMobil oil and gasoline products," the statement read.

As early as 1982, Exxon had predicted the precise amounts of carbon dioxide in the atmosphere by 2019, and the "catastrophic" effect these emissions, largely caused by fossil fuels, would have on the climate, the statement said.

Climate activists protest on the first day of the ExxonMobil trial outside the New York State Supreme Court building
Climate activists protest on the first day of the ExxonMobil trial outside the New York State Supreme Court building AFP / Angela Weiss

Rather than sharing this research, the statement said, "Exxon engaged in a decades-long campaign to deceive consumers and investors about the climate-related impacts of its products that continues to this day."

Environmental organizations have for years accused Exxon of hiding what it knew about the effects of its activities on the climate, and Massachusetts's lawsuit affirms the determination of several states governed by Democrats to take the oil giant to court over the allegation.

Exxon called the allegations "meritless."

"The Massachusetts attorney general's office has filed a baseless complaint three years after announcing its politically motivated investigation, during which they have not interviewed a single ExxonMobil employee or gathered one piece of evidence from the company," a spokesman said in a statement to AFP.

A similar lawsuit filed by New York's attorney general in October 2018 went to trial earlier this week.