US President Donald Trump has threatened to cut federal funding for the wildfires raging across California, in a Twitter spat with the state's Governor.

Key points: Donald Trump claimed the California Governor had done a "terrible job of forest management" in relation to the fires.

Donald Trump claimed the California Governor had done a "terrible job of forest management" in relation to the fires. However several of this year's major fires in the state have burned in unforested areas

However several of this year's major fires in the state have burned in unforested areas Governor Gavin Newsom "excused" the President from the conversation, saying: "You don't believe in climate change."

Californian Governor Gavin Newsom declared a statewide emergency last week, with around 40,000 hectares destroyed by wildfires fuelled by historic winds in recent weeks, and more than 11,000 people evacuated from their homes.

More than 370 structures have been destroyed since the fires started on October 23.

Donald Trump has threatened to pull fire aid to California. ( AP: Andrew Harnik )

In his first recent comments on the California fires, Mr Trump tweeted on Sunday that Democratic Mr Newsom had done a "terrible job of forest management".

Several of this year's major fires had burned in unforested areas.

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"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," he tweeted.

Mr Trump tweeted that when fires rage, the Governor comes to the Federal Government for help.

"No more," the President tweeted. "Get your act together Governor. You don't see close to the level of burn in other states.

In a tweet of his own, Mr Newsom replied: "You don't believe in climate change. You are excused from this conversation."

Californian authorities refer to a "new normal" when it comes to the devastating fires that have affected the state now for several years in a row.

"While wildfires are a natural part of California's landscape, the fire season in California and across the west [coast] is starting earlier and ending later each year," the Calfire website says.

Horses were evacuated onto trucks and floats as fires tore through ranches in the Simi Valley. ( AP: Ringo HW Chiu )

"Climate change is considered a key driver of this trend. Warmer spring and summer temperatures, reduced snowpack, and earlier spring snowmelt create longer and more intense dry seasons."

Those claims were backed up by a recent study published in the Proceedings of the National Academy of Sciences, which said increased temperatures due to global warming were one of the root causes of the huge wildfires sweeping over California, regardless of how wet the previous winter was.

Smoke and flames from the Maria Fire billow above Santa Paula in California on Thursday night. ( AP: Noah Berger )

The state controls a small percentage of California's forest land. The Federal Government manages most of it.

Neither of the two major fires currently burning in California are on forest land.

Firefighters have conducted backburning to slow the spread of the Kincade Fire. ( AP: Noah Berger )

Last year, Mr Trump made a similar threat as wildfires devastated Malibu and Paradise, California — accusing the state of "gross mismanagement" of forests.

At the time, Mr Newsom defended California's wildfire-prevention efforts while criticising the Federal Government for not doing enough to help protect the state.

By Sunday, authorities had lifted all evacuation orders as firefighters made progress on a large blaze that sent thousands fleeing homes and farms north-west of Los Angeles.

Pacific Gas & Electric started shutting off power on Saturday for an estimated 2.35 million people across 38 counties. ( AP: Jose Carlos Fajardo via East Bay Times )

Crews working in steep terrain were tamping down hotspots and keeping an eye on lingering gusts in mountain areas that could carry embers, said Ventura County Fire Captain Steve Kaufmann.

"I'd say we're cautiously optimistic," Mr Kaufmann said, citing calmer winds overall and rising humidity levels.

ABC/AP