Musk asked why "no one is even trying to assassinate Biden/Kamala" on X.
The White House on Monday decried a now-deleted post by Elon Musk on X as "irresponsible."
In the Sunday night post -- which he made after the second apparent assassination attempt on former President Donald Trump -- Musk, who owns the platform, responded to a user who asked, "Why they want to kill Donald Trump?"
In his post, Musk wrote, "And no one is even trying to assassinate Biden/Kamala."
Following intense backlash, Musk deleted the post and walked it back as a joke early Monday. The post got nearly 40 million impressions before being deleted.
"Well, one lesson I've learned is that just because I say something to a group and they laugh doesn't mean it's going to be all that hilarious as a post on X," Musk wrote.
"Turns out that jokes are WAY less funny if people don't know the context and the delivery is plain text," he added shortly after.
Responding to the post on Monday, the White House condemned Musk for having "joked about" or even "encouraged" violence.
"As President Biden and Vice President Harris said after yesterday's disturbing news, 'there is no place for political violence or for any violence ever in our country,' and 'we all must do our part to ensure that this incident does not lead to more violence,' the statement read.
"Violence should only be condemned, never encouraged or joked about. This rhetoric is irresponsible," the White House added.
Musk has endorsed Trump, and Trump has said he would tap Musk to lead a government efficiency commission if elected.