Former New Jersey Gov. Chris Christie (R), who has opened up in recent months about his own experience battling COVID-19 earlier this year, has released a new video urging all Americans to wear a mask amid the ongoing pandemic.

“This message isn’t for everyone. It’s for all those people who refuse to wear a mask,” he said in a video posted on Twitter Wednesday. “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.” 

I am very happy today for this ad to start to run on TV across America. I urge all Americans to learn from my experience and to, please, wear a mask and stay safe. pic.twitter.com/DGmOValDJo

— Governor Christie (@GovChristie) December 16, 2020

Christie was hospitalized for a week shortly after testing positive for COVID-19 in early October. At the time, he said he had checked himself into a hospital as a “precautionary measure,” citing his history with asthma. 

However, in comments detailing his experience in the ICU not long after his release, the former governor described the ordeal as “frightening.”

“I want people to understand it’s the most unpredictable and random virus you’ve ever seen. Don’t let your guard down. I made a huge mistake by taking that mask off. As tired as you are of wearing the mask, and washing your hands, you will take those days in a heartbeat compared to getting this disease,” he said then.

Christie had been diagnosed with the illness just days after it was confirmed President Trump and his wife Melania Trump had also been diagnosed with COVID-19.

About two weeks before his diagnosis, Christie was seen at the White House without a mask when the president announced Judge Amy Coney Barrett as his nominee to the Supreme Court.

After that event, Christie was also in close contact with the president to help him prepare for his first debate with then-Democratic nominee Joe Biden. He confirmed shortly before it was revealed he tested positive for COVID-19 that “no one was wearing masks in the room during that time when we were prepping the president.”

“The group was about five or six people in total,” he also said at the time.

Christie has since said he was “was wrong” to not wear a mask during either occasion. 

“I was wrong. I was wrong not to wear a mask at the Amy Coney Barrett announcement and I was wrong not to wear a mask at my multiple debate prep sessions with the president and the rest of the team.”

“I hope that my experience shows my fellow citizens that you should follow [Centers for Disease Control and Prevention] guidelines in public no matter where you are and wear a mask to protect yourself and others,” he also said in mid-October. 

In his video on Wednesday, Christie said he thinks “about how wrong it is to let mask-wearing divide us, especially as we now know you’re twice as likely to COVID-19 if you don’t wear a mask.”

“Because if you don’t do the right thing, we could all end up on the wrong side of history. Please, wear a mask,” he added.