Former Gov. Chris Christie told ABC News on Friday morning that no one was wearing a mask during President Donald Trump's debate prep.

Trump said early Friday that he and first lady Melania Trump have tested positive for the coronavirus. Trump’s positive test came just hours after he confirmed that senior aide Hope Hicks, who had traveled with him several times this week, had come down with the virus.

Some White House staffers knew by early Thursday that Hicks — who'd been traveling with President Donald Trump this week — had tested positive for the coronavirus, according to a CNN report. But nonetheless, Trump attended a fundraiser at his golf club in Bedminster later that day — just hours before testing positive himself.

Trump's Democratic opponent, former Vice President Joe Biden, said early Friday afternoon that he and his wife tested negative.

"I hope this serves as a reminder: wear a mask, keep social distance, and wash your hands," Biden said on Twitter.

The news of Trump's infection prompted Gov. Phil Murphy to urge those who were at the presidential fundraiser in Somerset County to get tested after offering the president and first lady "a speedy and complete return to good health."

Trump was last seen by reporters returning to the White House on Thursday evening and looked to be in good health. The New York Times on Friday reported that people close to the president said he was experiencing mild symptoms.

Chris Christie, left, and Rudy Giuliani listing to President Donald (AP Photo/Carolyn Kaster) Trump during a news conference at the White House

Christie told ABC News he had been at the White House off and on between Saturday and Tuesday helping Trump prepare for his debate with Democrat Joe Biden. The former governor said the last test he took was on Tuesday morning which was negative.

In a message on his Twitter account, Christie said he took a test on Friday morning but will not have the results until Saturday.

"I feel fine and have no symptoms," Christie said.

Christie told ABC News no one among the five or six people in the room during debate prep, including former New York Mayor Rudy Giuliani, were wearing masks. He also did not notice any coronavirus symptoms displayed by Hicks as of Tuesday when he left Washington.

Christie did not say if he was at the fundraiser late Thursday afternoon.

The Somerset County Department of Health, which is the public health department for Bedminster, and the state Department of Health have begun the contact-tracing investigation to determine the potential risk of exposure to attendees and staff at the facility, according to county spokesman Nathan Rudy.

"As a first step, the county has reached out to Trump National Golf Course with a request for lists of facility staff, event participants, and other people to help identify those who may have come in close contact with individuals that tested positive. The county Department will recommend appropriate public health control measures to identify close contacts based on the investigation," Rudy said.

New Jersey comedian Joe Piscopo said on his Twitter account that he was among those in attendance at the president’s fundraiser on Thursday.

“Had the privilege of being at a very social-distanced, private event just last night with the President. He was at the top of his game. He looked strong and sounded great,” the "Saturday Night Live" alum wrote, adding his best wishes for a “speedy recovery.”

Piscopo, who considered an independent run for governor in 2017, hosted his morning talk show on a New York City radio station on Friday morning.

An unnamed attendee told the New Jersey Globe that Trump left the event, which the individual said was completely outdoors, quickly and did not stop and chat with people on the way out like he normally does. Another attendee told the Globe there was more social distancing protocol than usual in place.

The Globe also reported that 180 people are expected to participate in the Gentlemen’s Invitational golf tournament today including several people who were at the fundraiser.

Biden and wife Jill sent well wishes on his Twitter account Friday morning before announcing their own test results.

"We will continue to pray for the health and safety of the president and his family," Biden wrote.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ