(CNN) Presidential candidate Jay Inslee said Wednesday that the Democratic National Committee's decision not to host a debate focused on climate change is "extremely disappointing."

The Washington state governor, whose Democratic presidential bid is focused on climate change, said the decision is "totally unacceptable" and told CNN's Erin Burnett on "Erin Burnett OutFront" that "the grass roots of our party are demanding that we pay attention to this existential threat."

"This is an issue upon which life depends itself and the continued civilization that we now enjoy," Inslee said.

He said in a news release that the DNC had told his campaign, "If we participated in anyone else's climate debate, we will not be invited to future debates."

He told Burnett, "That's outrageous to me, to muzzle candidates who want to go out and have this debate."

Read More