Elon Musk made fun of President Joe Biden for not congratulating SpaceX's Inspiration4 crew.
Musk said Biden was sleeping instead - evoking Donald Trump's "Sleepy Joe" nickname for Biden.
Musk also responded to a tweet attacking Biden and the United Auto Workers (UAW) union.
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Elon Musk made fun of President Joe Biden on Sunday, alluding to former President Donald Trump's nickname for Biden, "Sleepy Joe."
A Twitter user asked why Biden had not yet congratulated the crew of SpaceX's Inspiration4, the world's first all-civilian space mission. The crew landed on Saturday evening after orbiting the Earth for three days.
"He's still sleeping," Musk replied.
Musk's jibe alluded to the derogatory nickname Trump used for Biden during the 2020 presidential election.
Musk also responded to a meme on Twitter that appeared to attack the Biden administration's relationship with unions.
The meme showed a scene from the film "Alien." In the meme, a parasitic alien clamped onto a person's face was labelled "UAW" (United Auto Workers) and the person labelled "Biden."
Musk appeared to agree with the meme, commenting "seems that way," underneath it.
Musk last week criticized a Democrat-led bill that would give a $4,500 tax incentive to consumers buying electric vehicles built by unionized companies. He claimed, without evidence, that lobbyists for the UAW and Ford had written the bill.
Tesla has historically opposed unionization, and in March the National Labor Relations Board ordered Musk to remove a 2018 anti-union tweet and re-hire a fired union activist. Tesla appealed the ruling in April.
Biden appeared to snub Tesla at an August White House event that showcased electric vehicles. Musk tweeted at the time: "Seems odd that Tesla wasn't invited."
Musk also said in February that he'd spoken to the Biden administration about the possibility of introducing a carbon tax, but that the administration had dismissed it as too politically difficult.