The White House has vowed to fight the news media "tooth and nail" over what it sees as unfair attacks, with a top adviser saying the Trump administration had presented "alternative facts" to counter low inauguration crowd estimates.
On his first full day as president, Donald Trump said he had a "running war" with the media and accused journalists of underestimating the number of people who turned out on Friday for his swearing-in.
White House officials made clear no truce was on the horizon on Sunday in harsh television interviews.
"The point is not the crowd size. The point is the attacks and the attempt to delegitimize this president in one day. And we're not going to sit around and take it," Chief of Staff Reince Priebus said on Fox News.
"We're going to fight back tooth and nail every day and twice on Sunday," Priebus said.
He repeated White House press secretary Sean Spicer's charges on Saturday that the media had manipulated photographs to show smaller crowds at the inauguration.
Aerial photographs showed the crowds were smaller than at Barack Obama's 2009 inauguration.
Several of Spicer's statements about Friday's turnout were challenged in photographs and media reports.
His categorical assertion that "this was the largest audience to ever witness an inauguration - period" in particular was lampooned.
Asked why the press secretary was uttering provable falsehoods, White House senior adviser Kellyanne Conway fired back.
"If we are going to keep referring to our press secretary in those types of terms I think that we are going to rethink our relationship here," she said on NBC.
Conway responded to criticism that the new administration was focusing on crowds rather than on significant domestic and foreign policy issues by saying, "We feel compelled to go out and clear the air and put alternative facts out there."
Priebus and Conway focused on a press pool report that said the bust of civil rights icon Martin Luther King Jr had been removed from the Oval Office after Trump was sworn in as president.
The report on Friday night was quickly corrected, but Trump called out the reporter by name during a visit to the Central Intelligence Agency on Saturday.
Trump drew criticism from Democrats as well as former CIA Director John Brennan for his remarks at the agency, where he spoke before a memorial wall with stars representing personnel killed in action.
"President Trump ought to realise he's not campaigning anymore. He's president," Senate Democratic leader Chuck Schumer said.
"Instead of talking about how many people showed up at his inauguration, he ought to be talking about how many people are going to stay in the middle class and move into the middle class."