Elon Musk has brandished a chainsaw on stage and defended his slashing of US government spending in a bizarre appearance at a conservative conference.

Musk, who is spearheading Donald Trump’s massive effort to cut spending and downsize the US government, was given the chainsaw at the Conservative Political Action Conference in Washington, DC, on Thursday (US time) by Argentine President Javier Milei.

Milei used the chainsaw during his 2023 presidential campaign to symbolise his proposals to shred the bloated Argentine state.

Wearing sunglasses and his trademark black “Make America Great Again” hat, Musk swung the red chainsaw around at the end of his speech.

“This is the chainsaw for bureaucracy,” he yelled.

The cheering crowd gave the billionaire a standing ovation.

Musk’s Department of Government Efficiency has tapped into computer systems across multiple agencies with Trump’s blessing, digging into budgets and searching for what he calls waste, fraud and abuse.

Earlier this week, DOGE’s website claimed it found $US55 billion ($86 billion) in savings.

But there also concerns about mass layoffs of federal workers, closures of entire independent agencies and access to sensitive information. Several lawsuits have been filed contesting the layoffs and the access to federal government databases.

Earlier this week, a judge refused to immediately block the billionaire and DOGE from accessing government data systems or participating in worker layoffs.

US District Judge Tanya Chutkan found there were legitimate questions about Musk’s authority, but said there was no evidence of the kind of grave legal harm that would justify a temporary restraining order.

“Waste is pretty much everywhere,” Musk told the conference.

He also confirmed he was considering auditing the US central bank, the Federal Reserve

Musk slammed the previous Biden administration for its immigration policies, specifically naming an app that was used by nearly a million people to be allowed into the US on two-year permits with eligibility to work.

He accused Biden and Democrats of doing that as an “investment” to get more support in swing states.

“A lot of people don’t quite appreciate that this was an actual real scam at scale to tilt the scales of democracy in America,” Musk said before Newsmax host Rob Schmitt asked him, “Treason?”

Musk responded, “Treason.”

Asked to describe inside his mind, Musk said: “My mind is a storm. It’s a storm.”

Steve Bannon, a popular Trump ally, followed Musk’s appearance and acknowledged he was not the night’s top attraction.

“How did I draw the card to follow Elon Musk?” Bannon said about a man he has frequently criticised as insufficiently loyal to Trump.

“C’mon man! You bring out the world’s wealthiest guy, Superman. I’m supposed to follow it? I’m just a crazy Irishman!”

-with AAP