(CNN) President Donald Trump, in an attempt to tout his plan to send astronauts back to the moon and eventually Mars, slammed his 2016 opponent Hillary Clinton in a speech in Miramar, California, on Tuesday.

It's been more than a year since the 2016 election. But Trump said that his space plan was more fulsome than Clinton's, even though the former secretary of state said during her campaign that she would like to make "human exploration of Mars a reality."

"You wouldn't be going to Mars if my opponent won," Trump claimed on Tuesday. "You wouldn't even be thinking about it."

The comments came during a speech before military members in California, where Trump was making his first trip to the state as President. He visited the US-Mexico border earlier in the day to tout his border wall plan.

Late last year, Trump directed NASA's acting administrator, Robert M. Lightfoot Jr., to "lead an innovative space exploration program to send American astronauts back to the moon, and eventually Mars" during a White House signing ceremony in December.

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