Biden prioritizes climate crisis by naming John Kerry special envoy - CNN

"This marks the first time that the NSC will include an official dedicated to climate change, reflecting the president-elect's commitment to addressing climate change as an urgent national security issue," the Biden transition team said in a statement.

Bernie Sanders of Vermont, during his first presidential campaign in 2016, called climate change the foremost national security crisis, he was pilloried as not being serious about foreign policy.

Five years later, the White House will have a special envoy for climate with a seat at National Security Council meetings.

Kerry has long worked on climate issues.

The co-founder and executive director of a leading progressive group on climate, Sunrise Movement, congratulated Kerry on his appointment and said the creation of the role was an "encouraging sign." Varshini Prakash, who served alongside Kerry on the unity task force, described him as "committed to engaging and listening to young voices -- even when we might not always agree -- and ensuring we have a seat at the table."

But Prakash said the one role was "not enough" and that Biden's White House "must also include a domestic counterpart reporting directly to the President to lead an Office of Climate Mobilization."

The President-elect is expected to have a White House climate director working on domestic issues who will be on equal footing with Kerry, a source familiar with the matter confirmed to CNN.