JPMorgan Asset Management, which manages $3.1 trillion in assets, said it had decided not to renew its membership of the Climate Action 100+ investor group after "significant investment" in its stewardship team over the last couple of years.

"The firm has built a team of 40 dedicated sustainable investing professionals, including investment stewardship specialists who also leverage one of the largest buy side research teams in the industry," it said in a statement.

"Given these strengths and the evolution of its own stewardship capabilities, JPMAM has determined that it will no longer participate in Climate Action 100+ engagements."

The move is the latest pullback by U.S.-based financial firms from group initiatives that have emerged as part of the world's fight against climate change, amid legal threats from some U.S. states that membership could breach antitrust rules.

A spokesperson for CA100+ confirmed that JPMorgan Asset Management had left the voluntary group, becoming one of 14 to do so since it was launched in 2017, including BlueBay Asset Management, Loomis Sayles and Lord Abbett.

It follows the adoption last year of 'phase 2' guidelines for CA100+ members, to run until 2030, in which members were urged to "go from words to action" and hold laggard companies to account over weak climate planning.

This followed the decision by many CA100+ members to oppose shareholder resolutions calling for faster climate action at company annual general meetings in recent years.

Despite the exits, membership of CA100+ has grown strongly and last autumn saw 60 join, the initiative's spokesperson said, taking total membership to more than 700 firms running more than $60 trillion in assets.

The news was first reported by the Financial Times.

(Reporting by Simon JessopEditing by Tommy Reggiori Wilkes, Kirsten Donovan)

By Simon Jessop