Shares of Tesla slid over 8% on Thursday as CEO Elon Musk and President Donald Trump traded barbs over the spending bill making its way through Congress.

Trump spoke from the Oval Office Thursday and said Musk was upset that EV credits were not included in the bill.

“Elon and I had a great relationship. I don’t know if we will anymore,” Trump said in the Oval Office on Thursday. “I was surprised.”

“Whatever,” Musk fired back as the president spoke.

“Without me, Trump would have lost the election, Dems would control the House and the Republicans would be 51-49 in the Senate,” he posted on X.

Musk, the world’s richest man, in recent days has threatened to make lawmakers who vote for the bill face primary elections and called the bill a “disgusting abomination,” marking a significant shift in his comments about the administration.

The fall in shares comes after the EV maker saw a 22% rally in May despite weak sales numbers, with Musk wrapping up his time as head of Trump’s so-called Department of Government Efficiency, or DOGE.

Shares are down more than 20% this year and well off the high of $488.54 reached Dec. 18.

Since Musk’s special government employee term ended Friday, he’s appeared at odds with the Trump administration and gone on a full assault against the president’s signature tax-cut bill.

“One of the things about Elon is when he goes all in, he goes all in,” Walter Isaacson, author of a Musk biography, told CNBC’s “Squawk Box” on Thursday.

“He is somebody who’s not exactly calibrated in these things and he is seriously upset,” Isaacson said.Trump spoke after days of Musk condemning the bill on social media.

Musk last week left his temporary government post overseeing DOGE, the Trump administration’s effort to slash federal spending and employee headcounts. Musk also was the biggest financial backer of Trump’s 2024 campaign, spending more than $250 million on that effort.

“You know, I’ve always liked Elon,” said Trump on Thursday. “I’d rather have him criticize me than the bill, because the bill is incredible.

“Elon is upset because we took the EV mandate, and you know, which was a lot of money for electric vehicles,” Trump said. “And you know, they’re having a hard time, the electric vehicles, and they want us to pay billions of dollars in subsidy.”

“Elon knew this from the beginning,” Trump said, referring to the elimination of the tax credits in the bill for electric vehicles. “He knew it ... a long time ago.”