President Donald Trump offered a vague threat to pull California's federal aid for combating dangerous wildfires on Sunday, sparking a response from Democratic Gov. Gavin Newsom as the pair traded barbs through the day.

"The Governor of California, @GavinNewsom, has done a terrible job of forest management," Trump tweeted early Sunday. "I told him from the first day we met that he must 'clean' his forest floors regardless of what his bosses, the environmentalists, DEMAND of him. Must also do burns and cut fire stoppers. Every year, as the fire’s rage & California burns, it is the same thing-and then he comes to the Federal Government for $$$ help. No more. Get your act together Governor. You don’t see close to the level of burn in other states."

It's unclear what fires Trump was referred to as the blazes that have ravaged California in recent weeks did not burn down any forests.

Newsom on Sunday fired back, pointing to Trump's years-long denial of climate change and its environmental effects.

"You don’t believe in climate change," Newsom tweeted. "You are excused from this conversation."

Trump revisited the subject later Sunday afternoon, speaking to reporters on the White House South Lawn. Sunday was the first time Trump made significant mention of the California wildfires since the large-scale Kincade Fire broke out late last month.

President Donald Trump and then-Governor-elect Gavin Newsom visit a neighborhood impacted by the wildfires in Paradise, Calif., on Nov. 17, 2018. Evan Vucci / AP file

"You've got fires eating away at California every year because management is so bad," Trump said. "The governor doesn't know; he's like a child, he doesn't know what he's doing. And I've been telling them this for two years. They've got to take care of it. Every year it's always California, it's rarely somebody else or someplace else."

Trump has repeatedly taken aim at California since taking office nearly three years ago, often over environmental issues. He has previously criticized the state for not properly "raking" the forest floors to help prevent fires and threatened to cut off Federal Emergency Management aid. Experts have pointed to climate change-related reasons for the uptick in wildfire frequency and strength in recent years.

Newsom last month praised the federal government's efforts in assisting with wildfire management.

"I have nothing but good things to say about the federal government’s support," Newsom said, per the Los Angeles Times. "In fact, the Homeland Security acting director proactively called me two days ago to check in ... Hats off to them."