Vice President Mike Pence said on Thursday that the Trump administration wants to send astronauts to the moon “not only to leave behind footprints and flags,” but to set the stage for the U.S. to send people to Mars.

His statement echoes a recent Wall Street Journal op-ed in which he wrote that America’s “pre-eminence in outer space is now under threat” and that “American prosperity and security depend on U.S. leadership in space.”

Pence believes that the U.S.’s space program reached its pinnacle in 1969, when U.S. astronauts landed on the moon. With that achievement, the U.S. claimed “its rightful place as the undisputed leader in the exploration of the heavens,” he wrote.

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Now, however, Pence is afraid the space program risks being overshadowed by efforts by Russia and China.

He lamented the danger during a National Space Council meeting on Thursday, the first meeting of the re-launched group in over two decades. President Donald Trump reinstated the space advisory council in August after it was disbanded during President George H. W. Bush’s administration.

“The United States has not sent an American astronaut to low-Earth orbit in 45 years,” said Pence, who is the National Space Council’s chairman.

In Pence’s opinion, it’s especially troubling that America has “agreed to pay Russia to hitch a ride on their rockets to the International Space Station.” The U.S. has frequently used the space station after ending the space shuttle program in 2011.

“In the absence of American leadership, other nations have seized the opportunity to stake their claim in the infinite frontier,” Pence said. “Rather than lead in space, too often we’ve chosen to drift.”

He also cited the danger of leaving space exploration to Russia and China. They’re “pursuing a full range of anti-satellite technology to reduce U.S. military effectiveness, and they’re increasingly considering attacks against satellite systems as part of their future warfare doctrine,” he said.

Still, Pence failed to outline specific plans to send astronauts to the moon. For instance, he did not mention funding for a moon program or any expected date for any landing. The Trump Administration’s fiscal 2018 budget request included $19.1 billion for NASA, which as CBS News noted in May, was “$561 million decrease over previously enacted levels that would reduce the number of Earth science missions, eliminate the agency’s education office and do away with the Obama administration’s plans to robotically retrieve a piece of an asteroid as a precursor to eventual flights to Mars.”

Former President Barack Obama previously dismissed the idea of sending people to the moon, saying in 2010 that “we’ve been there before.” Instead, Obama wanted to focus attention on Mars, as he explained in a CNN op-ed last fall.

“We have set a clear goal vital to the next chapter of America’s story in space: sending humans to Mars by the 2030s and returning them safely to Earth, with the ultimate ambition to one day remain there for an extended time,” Obama wrote.

Astronaut Buzz Aldrin, one of the astronauts on the first moon mission, supported Obama’s space policies and his decision against returning astronauts to the moon. “The truth is, that we have already been to the Moon – some 40 years ago,” he said in 2010,

“A near-term focus on lowering the cost of access to space and on developing key, cutting-edge technologies to take us further, faster, is just what our Nation needs to maintain its position as the leader in space exploration for the rest of this century,” Aldrin said.

Other attendees of the National Space Council meeting included representatives of the Elon Musk-backed space transportation company SpaceX, the Jeff Bezos founded aerospace company Blue Origin, Lockheed Martin, and Boeing.