The top US broadcast regulator on Saturday threatened media outlets over negative coverage of the Middle East war, after President Donald Trump slammed critical headlines from the "Fake News Media."

The president since his first term has derided mainstream media as "fake news" and has sued major outlets over what he sees as unfair coverage.

Brendan Carr, chairman of the Federal Communications Commission (FCC) -- which oversees US radio, television and internet media -- said broadcasters risked losing their licenses over news coverage.

"The law is clear. Broadcasters must operate in the public interest, and they will lose their licenses if they do not," Carr said in a post on X.

"Broadcasters that are running hoaxes and news distortions -- also known as the fake news -- have a chance now to correct course before their license renewals come up."

Carr's statement did not single out any news outlet, but it included a Trump social media post in which the president called out "an intentionally misleading headline by the Fake News Media" on five tanker planes hit by Iran strikes in Saudi Arabia.

The Foundation for Individual Rights in Education (FIRE), a US-based free speech advocacy organization, slammed Carr's "authoritarian" warning as "outrageous." 

"When the government demands the press become a state mouthpiece under the threat of punishment, something has gone very wrong," it said on X.

Since Israel and the United States first launched strikes on Iran on February 28, both Trump and Pentagon chief Pete Hegseth have regularly swatted down critical stories as "fake news." 

On Friday both the Pentagon and White House called out broadcaster CNN after it ran a story suggesting Washington had underestimated Iran's ability to disrupt global oil traffic in the Strait of Hormuz. 

"This story is 100% FAKE NEWS," Press Secretary Karoline Leavitt said in a post on X.

Carr last year threatened the broadcast license of ABC following comments made by late-night talk show host Jimmy Kimmel on the assassination of right-wing activist Charlie Kirk. 

ABC briefly pulled Kimmel's show after the threats, leading to widespread outcry before it returned to air.