Supreme Court Justice Ruth Bader Ginsburg. AP Photo/Charles Rex Arbogast

President Donald Trump has already appointed one Supreme Court justice, and he is reportedly telling people he believes he will appoint three more.

Multiple sources told Jonathan Swan of the news website Axios that Trump was openly predicting he would be able to fill four Supreme Court seats as president.

One of Trump's signature victories as president has been the appointment of Justice Neil Gorsuch, who filled the seat left vacant by the death of Justice Antonin Scalia in February 2016. The battle to fill Scalia's seat was contentious, with Senate Majority Leader Mitch McConnell refusing to consider a nominee proposed by President Barack Obama.

Justice Anthony Kennedy, 81, is rumored to be thinking about retirement. Trump, according to Axios, also thinks he'll be able to replace Justices Ruth Bader Ginsburg and Sonia Sotomayor, citing their health.

Talking about the 84-year-old Ginsburg, one source told Axios, Trump said: "What does she weigh? Sixty pounds?"

Trump has talked about Sotomayor's Type 1 diabetes, according to Axios, telling the source: "Her health, no good. Diabetes."

Sotomayor, 63, was appointed by Obama and is one of the younger justices on the court.

If Trump is able to replace Kennedy, Ginsburg, and Sotomayor, he could radically change the makeup of the Supreme Court.

Kennedy, who was appointed by Republican President Ronald Reagan, is a moderate conservative, often providing the deciding vote on 5-4 decisions.

Both Ginsburg and Sotomayor were appointed by Democrats — Bill Clinton and Obama, respectively — and are considered liberal justices. Replacing even one would allow Trump to shift the balance of the court to the right.

Justice Stephen Breyer, another liberal, is 79 years old.