Japan could be a key indicator when it comes to predicting a pandemic-level spread of the deadly coronavirus, former FDA commissioner Scott Gottlieb told CNBC on Tuesday.

Japan appears to be "on the cusp of a large outbreak and maybe epidemic growth in Japan. We need to watch that very closely. They've had a doubling of cases just in the last four days" with a total of 59 confirmed cases and one death so far, Gottlieb said on "Squawk Box."

If other countries report sharp rises in COVID-19 cases, Gottlieb said it could be a sign that the new virus can't be controlled on a global scale. The CNBC contributor said earlier in February it's likely the flu-like virus will grow into a pandemic but avoid becoming an epidemic in the United States.

A pandemic is the worldwide spread of a new disease, according to the World Health Organization. An epidemic is an often sudden increase in the number of cases of a disease above what is normally expected in a population in an area, according to the U.S. Centers for Disease Control and Prevention.

Dr. Syra Madad, an expert in public health and special pathogen response, said that while it's still early in the outbreak, a pandemic could be near.

"We're really closing in on the tipping of this being declared a pandemic," Madad said on "Squawk Box."

As of Tuesday, more than 73,400 cases of COVID-19 have been confirmed, including at least 1,874 deaths. The vast majority are in China. The World Health Organization, which has declared the virus a global health emergency, said there's been more than 150 coronavirus cases in about two dozen countries outside of China.

French Health Minister Olivier Veran said Tuesday the coronavirus poses a "credible risk" of escalating into a global pandemic. Veran told France Info radio that the prospect of the coronavirus spreading worldwide was "both a working assumption and a credible risk."