Joe Biden said Monday that expanding his climate platform will be a "key objective" in the coming months and laid out broad areas where the plan could see changes.

Driving the news: The announcement came in the presumptive Democratic nominee's statement accepting the endorsement of the League of Conservation Voters Action Fund.

"I have asked my campaign to commence a process to meaningfully engage with more voices from the climate movement — including environmental justice leaders and worker organizations, and collaborate on additional policies in areas ranging from environmental justice to new, concrete goals we can achieve within a decade, to more investments in a clean energy economy."

— Joe Biden

Why it matters: It's the second sign in recent days that he is likely to alter his platform, which some green activists see as too modest even though it goes much further than Obama-era initiatives.

Sen. Bernie Sanders' endorsement of Biden last week included the announcement of plans to form joint policy "task forces," with climate among the topics.

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