SpaceX and Tesla CEO Elon Musk took shots at President Joe Biden on Sunday for failing to praise SpaceX for its all-civilian mission to orbit the Earth. When fans pointed out on Twitter that Biden had failed to acknowledge the spaceflight, Musk quipped: “He’s still sleeping.”

CNBC reports that SpaceX and Tesla CEO Elon Musk was unhappy with President Joe Biden’s failure to acknowledge the recent SpaceX civilian mission to orbit over the weekend.

WASHINGTON, DC – AUGUST 26: U.S. President Joe Biden speaks about the situation in Afghanistan in the East Room of the White House on August 26, 2021 in Washington, DC. At least 12 American service members were killed on Thursday by suicide bomb attacks near the Hamid Karzai International Airport in Kabul, Afghanistan. (Photo by Drew Angerer/Getty Images)

Elon Musk strikes a SpaceX pose (pool/Getty)

One of Musk’s Twitter followers asked him: “The President of the United States has refused to even acknowledge the 4 newest American astronauts who helped raise hundreds of millions of dollars for St. Jude. What’s your theory on why that is?”

Musk responded “He’s still sleeping,” which appeared to be reminiscent of former President Donald Trump’s nickname for Biden, “Sleepy Joe.”

Over the weekend, SpaceX returned its Crew Dragon spacecraft from orbit. The craft carried four members of the Inspiration4 mission back to Earth after spending three days in space. One of the major goals of the mission was to raise $200 million for St. Jude Children’s Research Hospital.

By Saturday, the mission had raised $160.2 million. Following the return of the spacecraft to Earth, Musk pledged to contribute $50 million personally, bringing the total campaign funds to $210 million.

Musk has previously made similar remarks about public figures. In April in response to a tweet from New York Times tech columnist Kenneth Chang, Musk took shots at Amazon and Blue Origin founder Jeff Bezos.

Chang shared a story claiming that Bezos’ space exploration company had filed a protest against NASA’s awarding of the lunar lander contract to SpaceX. In response, Musk appeared to attack Bezos’ manhood, tweeting: “Can’t get it up (to orbit) lol”

Read more about Musk’s remarks towards President Biden at CNBC here.

Lucas Nolan is a reporter for Breitbart News covering issues of free speech and online censorship. Follow him on Twitter @LucasNolan or contact via secure email at the address lucasnolan@protonmail.com