Melania Trump
Melania Trump Reuters

US First lady Melania Trump on Thursday fired back at an anonymous administration official who published an op-ed in The New York Times.

"Freedom of speech is an important pillar of our nation's founding principles and a free press is important to our democracy. The press should be fair, unbiased and responsible," she told CNN in a statement.

"To the writer of the op-ed -- you are not protecting this country, you are sabotaging it with your cowardly actions," added Trump.

"Unidentified sources have become the majority of the voices people hear about in today's news. People with no names are writing our nation's history. Words are important, and accusations can lead to severe consequences," she added. "If a person is bold enough to accuse people of negative actions, they have a responsibility to publicly stand by their words and people have the right to be able to defend themselves."

The op-ed author was identified as a "senior Trump administration official" who said they were part of an internal "resistance" working to thwart parts of President Donald Trump's agenda and block his worst impulses.

White House press secretary Sarah Huckabee Sanders said the author is a “coward” who should “do the right thing and resign.”

The official, she continued, has chosen to “deceive, rather than support, the duly elected President of the United States.”

President Donald Trump responded on Twitter following the publication of the anonymous editorial, calling the author “gutless”.

“Does the so-called 'Senior Administration Official' really exist, or is it just the Failing New York Times with another phony source? If the GUTLESS anonymous person does indeed exist, the Times must, for National Security purposes, turn him/her over to government at once!” he wrote.