"I made a speech. I looked out, the field was, it looked like a million, million and a half people," he told CIA staff during a visit to the agency's headquarters on his first full day in office.
"They showed a field where there were practically nobody standing there. And they said, Donald Trump did not draw well," he added.
Trump said one network estimated turnout at 250,000.
"Now, that's not bad. But it's a lie," Trump said. He insisted there were people stretching from the steps of the Capitol, where he spoke, along 20 blocks back to the Washington Monument.
"So we caught them and we caught them in a beauty and I think they're going to pay a big price," said Trump.
The National Mall at the inaugurations of President Barack Obama, above, on Jan. 20, 2009, and President Donald Trump, below, on Jan. 20, 2017. (AAP) Source: AP
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Washington city authorities do not provide official crowd counts but TV footage clearly showed the crowd did not in fact stretch all the way to the Washington Monument and aerial photos indicate that turnout Friday was significantly smaller than during Barack Obama's second inauguration, in 2013.
Trump's latest attack on news organizations came during a rambling aside as he visited CIA headquarters on a fence-mending mission after his public rejection of the assessment by US intelligence agencies that Russia meddled to try to help him win the November election.
Trump spoke while standing in front of a spot sacred to the CIA -- a wall with stars engraved for employees killed while serving the country.
After saying he supported the CIA fully, Trump eventually returned to the issue of media coverage of his inauguration and said the National Mall, divided up into sections for Friday's ceremony, was uniformly crammed with people.
"You saw that. Packed. I get up this morning, I turn on one of the networks, and they show an empty field. I'm like, wait a minute," he said
