Nearly 100,000 acres have been destroyed by wildfires in recent weeks, and thousands have been forced from their homes.
Mr Trump blamed Governor Gavin Newsom, a Democrat, saying he had done a "terrible job of forest management".
Several of this year's major wildfires have burned in unforested areas.
"Every year, as the fire's (sic) 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," Mr Trump wrote on Twitter.
Mr Newsom, who has been highly critical of Mr Trump's environmental policies, responded: "You don't believe in climate change. You are excused from this conversation."
Increased temperatures due to global warming are causing huge wildfires in California, according to a recent study published in the Proceedings of the National Academy of Sciences.
Drier, warmer conditions lead to vegetation drying out and becoming more flammable.
President Trump made a similar threat to cut federal aid in 2018, when the most deadly fire in California's history killed 86 people.
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