Stephen Bannon said the media should "keep its mouth shut and just listen for a while"
One of Donald Trump's senior advisers has described the media as the 'opposition party' of the new administration.
Stephen Bannon - the former head of the right-wing Breitbart News website - is serving as President Trump's chief strategist.
In remarks quoted by the New York Times, Mr Bannon said: “The media should be embarrassed and humiliated and keep its mouth shut and just listen for a while."
Urging reporters to quote his remarks, he added: "The media here is the opposition party. They don’t understand this country. They still do not understand why Donald Trump is the president of the United States.”
The remarks round out a first week that saw the Trump administration on the offensive against media outlets.
In a fiery first statement to the media on Saturday, Press Secretary Sean Spicer accused the media of inaccurately reporting crowd sizes at the inauguration last Friday - despite evidence showing turnout was lower than in previous years.
Mr Spicer said: "There's been a lot of talk in the media about the responsibility to hold Donald Trump accountable. And I'm here to tell you that it goes two ways. We're going to hold the press accountable, as well."
In a widely reported interview with NBC the following day, Trump aide Kellyanne Conway suggested the administration was providing "alternative facts" about inauguration sizes.
Mr Trump, meanwhile, has also criticised the media in some of his first remarks as President.
Speaking at the CIA headquarters over the weekend, he suggested: "I have a running war with the media. They are among the most dishonest human beings on Earth."
The Reporters Without Borders group has raised concerns over this week's incidents.
Delphine Halgand, Director of RSF North America, said: "The press freedom predators of the world are watching Trump and taking notes.
"It’s terrifying to think how much more brazen they will be in their attacks on journalists around the world now that the leader of the United States of America is setting a terrible example.”