Former White House chief of staff Mark Meadows reportedly reveals in a new book that former President Trump tested positive for the coronavirus three days before his first debate against then-Democratic presidential nominee Joe Biden.

In "The Chief’s Chief," Meadows writes that although Trump was aware that in order to participate in the debate each candidate had to “to test negative for the virus within seventy two hours of the start time ... Nothing was going to stop [Trump] from going out there," The Guardian, which obtained a copy of the book, reported.

Shortly after getting the positive result, Trump reportedly tested again and received a negative result.

According to Meadows, Trump’s initial positive test on Sept. 26, 2020, shocked the White House. He recalled the White House doctor calling as Trump was scheduled to take off on Marine One, according to The Guardian.

“Stop the president from leaving,” Meadows says Sean Conley told him. “He just tested positive for Covid.”

Meadows later reportedly added that the former president's reply to the news “rhyme[d] with ‘Oh spit, you’ve gotta be trucking lidding me.’ ”

It was determined at that time that the positive test came from an old model kit and Trump would be tested again using “the Binax system," Meadows said, according to The Guardian.

"We were hoping the first test was a false positive," he added.

Meadows recalled calling the president back with the news of the negative test, which he said Trump took as “full permission to press on as if nothing had happened," the news outlet noted.

The former chief of staff reportedly said, however, that he still “instructed everyone in his immediate circle to treat him as if he was positive” throughout a scheduled trip to Pennsylvania.

“I didn’t want to take any unnecessary risks,” Meadows writes, “but I also didn’t want to alarm the public if there was nothing to worry about — which according to the new, much more accurate test, there was not.”

It was not until Oct. 2, days after the debate with Biden, that Trump announced that he had tested positive for COVID-19, and he went to the hospital later that day.

"The story of me having COVID prior to, or during, the first debate is Fake News," Trump said in a statement.

"In fact, a test revealed that I did not have COVID prior to the debate," he added.

--Updated at 9:21 a.m.