Trump added: "I don't think he's a smart person, but he's got a loud voice".
Mr Acosta, CNN's chief White House correspondent, said he was informed by Secret Service officers that he could not enter for his scheduled 8pm broadcast. The reporter was in the midst of a terse back-and-forth with Trump, whom he was trying to ask a question about a migrant caravan heading for the U.S. "But I watch you a lot and you ask a lot of stupid questions", Trump said, jabbing his finger at her before turning and walking away.
"He gets paid to do this", Mr. Trump said.
"The fact that the White House press secretary is promoting this doctored video is reprehensible, and grounds for dismissal".
"You have to treat the White House of the office of the presidency with respect".
Earlier in the week, Trump asked CNN contributor April Ryan to "sit down" when she was at the briefing. Trump on Wednesday accused Alcindor of asking a racist question when she inquired about the president receiving support from some white nationalists.
CNN Vice President of Communications and Digital Partnership Matt Dornic said it was "absolutely shameful" that Sanders had released a "doctored" video.
The video tweeted by Sanders does not have any audio, which would make it easier to tamper with, said Shapiro. But all three of the latest examples fall into the categories of people - journalists, women, African-Americans - for whom Trump has reserved special nastiness.
Donald Trump is not backing down from personal attacks on reporters.
Trump said he hadn't made a decision when asked by a reporter how long Acosta would remain in the "penalty box".
Ryan phoned in to CNN to respond to the President's comments. "He's a very unprofessional guy", Trump said. I mean, she intentionally disseminated doctored video to discredit a reputable journalist.
Video clips also showed an unnamed female White House intern unsuccessfully attempting to reclaim the microphone from Acosta.
White House counselor Kellyanne Conway told "Fox and Friends" on November 8 "The reporter from NBC was already standing, getting ready to ask his question, and she was just doing her job, which was to reclaim the microphone that belongs to the federal government".
Addressing a question about suspending press credentials for other reporters, Trump did not rule out the idea. "The way you treat other people is frightful!"