• The friendship between Elon Musk and Donald Trump publicly unravelled on Thursday.
• It all started when Musk criticized Trump's "Big Beautiful Bill."
• Here's what business leaders like Mark Cuban and Bill Ackman have to say about the breakup.

Amid a dramatic falling out between Donald Trump and his "first buddy," Elon Musk, some of the business world's most influential voices are weighing in.

The relationship between the president and his once-close ally imploded on Thursday as they clashed publicly over Trump's "Big Beautiful Bill."

Musk, who stepped down from his role at DOGE in May, took to X to criticize the bill, calling it the "Debt Slavery Bill" and the "Big Ugly Spending Bill."

In response, Trump fired back at Musk during a White House event. He also defended the bill on Truth Social, while threatening to cancel Musk's government contracts.

Musk saw his net worth fall by $34 billion on Thursday, per the Bloomberg Billionaires Index. Tesla shares were also down by more than 14%.

Here's what several business leaders have to say about the row.

Mark Cuban

Amid his feud with Trump, Musk proposed creating a new political party for "the middle" in a poll on X.

Mark Cuban appeared to endorse the idea, quoting Musk's post and replying with three check marks.

The former "Shark Tank" star previously said he's "not a fan of either party," but would run as a Republican if he wanted to join politics.

Bill Ackman

Hedge fund billionaire Bill Ackman voiced his support for both Trump and Musk on X, calling on the two to put aside their differences and "make peace for the benefit of our country."

Ackman, who had endorsed Trump for his 2024 presidential bid, wrote: "We are much stronger together than apart."

"You're not wrong," Musk responded.

Paul Graham

Paul Graham, cofounder of the startup accelerator Y Combinator, also weighed in on the public feud between the president and the Tesla CEO.

"A lot of people seem to be treating this as if it were just a beef. But the underlying allegation is a very serious one. If it's true, Trump is surely going to have to resign," he wrote in a post on X.

Graham did not specify what allegation he was referring to.

Hours before Graham made his post, Musk went on X and accused Trump of withholding information about Jeffrey Epstein.

"Time to drop the really big bomb: @realDonaldTrump is in the Epstein files. That is the real reason they have not been made public. Have a nice day, DJT!" Musk wrote on X.

Graham told Musk in February that he should work with the government "carefully" because it's not "just a company."

A representative for Graham did not immediately respond to a request for comment from Business Insider.

• Bill Ackman said a fear of looking weak is preventing the US and China from cutting tariffs.
• The billionaire hedge fund manager said tariffs should fall to "more reasonable levels" of 10% to 20%.
• He also questioned the belief that China can "win" a trade war with the US.

Billionaire hedge fund manager Bill Ackman has said that China and the United States should dramatically cut their tariffs on one another, and only the fear of "looking weak" is stopping them.

Ackman, the CEO of Pershing Square who supported President Donald Trump during the election, made the comments as imported Chinese goods entering the United States face a 145% tariff and American goods entering China face a 125% tariff.

A 10% baseline tariff on all imports into the United States remains in effect, while Trump has paused his raft of country-specific tariffs.

Ackman, who thanked Trump for announcing a 90-day pause on his proposed "reciprocal" tariffs earlier this month, posted on X on Saturday that tariffs were "very damaging in the short term to companies that rely on China for a large percentage of their goods."

He added China and the United States should reduce tariffs to "more reasonable levels — say 10% to 20% — as quickly as possible."

"The only thing stopping the reduction in tariffs to a more sensible level is the fear on the part of both countries' leadership of looking weak," he said.

"A pause, however, would not be a sign of weakness because it requires both countries to take down their tariffs. It is just common sense," he added.

Ackman also questioned the view that China could "win" a trade war with the United States.

"The problem with this assessment is that, the longer the tariffs persist, the more rapidly every company that has a supply chain based in China relocates it to India, Vietnam, Mexico, the U.S. or some other country," Ackman wrote.

"This is true for US and non-US companies. As a long-term player, China must understand this dynamic," he continued.

Ackman added that whatever happened, companies would no longer be willing to keep their supply chains in China. "That cake is already baked," he added.

Trump and China's leadership made conflicting statements this week about the status of trade talks.

"We're meeting with China," Trump said in an interview with "Time" magazine, which was published on Friday but held on Tuesday.

On Thursday, two Chinese officials said there were no ongoing talks.