TRENTON, N.J. (CBSNewYork) — After recovering from the coronavirus, former New Jersey Gov. Chris Christie is starring in a new ad urging people to wear a mask.

Christie posted the ad on Twitter, saying it will air across the nation.

“You know, lying in isolation in ICU for seven days, I thought about how wrong I was to remove my mask at the White House. Today, I think about how wrong it is to let mask-wearing divide us,” Christie says in the ad.

The former governor got infected in October after he attended a ceremony at the White House where few people wore masks.

MORE: Chris Christie’s Bout With COVID A Stark Reminder Of The Dangers Of Letting Your Guard Down

It’s unclear how Christie got the virus, but he urged Americans to “learn from his experience.”

MORE FROM CBS NEW YORK