"And I don't see any numbers that dispute that when you add up attendance, viewership, total audience in terms of tablets, phones, on television. I'd love to see any information that proves that otherwise."
Spicer did not address some of the other questionable data points that he listed on Sunday, when he summoned the press corps to deliver a statement that criticised coverage of Trump's inauguration and argued that Trump had "the largest audience to ever witness an inauguration, period, both in person and around the globe."
While criticising the media for reporting crowd counts, because the US Park Service does not provide them, Spicer insisted that when the President took the oath of office, there were 720,000 people sitting in three sections on the mall. He implied that aerial photos of the crowd could not be trusted because a white ground covering was used, accentuating empty spaces. Spicer left that Sunday briefing without taking questions from reporters.
Today, Spicer took dozens of questions from reporters during a briefing that lasted more than 90 minutes. He opened the briefing - his first official one - by vaguely joking about his controversial statement and saying that his Twitter feed proves that he is not the most popular press secretary. But soon, a reporter pressed Spicer on what happened and asked if he plans to always be truthful and never knowingly say something that is not factual.
"Our intention is never to lie to you," Spicer said.
"You're in the same boat: I mean, there are times when you guys tweet something out or write a story and you publish a correction. That doesn't mean that you were intentionally trying to deceive readers and the American people, does it? And I think that we should be afforded the same opportunity.
"There are times when we believe something to be true or we get something from an agency or we act in haste because the information available wasn't complete but our desire to communicate with the American people and make sure that you have the most complete story at the time, and so we do it.
"But, again, I think that when you look net-net, we're going to do our best every time we can. I'm going to come out here and tell you the facts as I know them, and if we make a mistake, I'll do our best to correct it."
Spicer continued to push reporters to hold themselves to the same levels of accountability that they hold the White House. He again pointed to an inaccurate report on Saturday by a reporter who mistakenly thought the bust of Martin Luther King jnr had been removed from the Oval Office. When it was revealed that the bust was still there, the reporter quickly issued a correction and an apology to his colleagues. Spicer responded on Twitter on Saturday: "Apology accepted."
"We had a tweet go out about Martin Luther King - think about how racially charged that is," Spicer said today. "And someone rushes out and says to the entire press corps that the president of the United States has removed the bust from his office."
Spicer said that while the reporter apologised to his colleagues, "Where was the apology to the President of the United States? Where was the apology to millions of people who read that and thought how racially insensitive that was. Where was that apology?"
