Washington D.C. - The former Trump administration official who went by the alias 'Anonymous' and published an unaccredited essay in the New York Times critical of the president, revealed his identity on Wednesday.

Miles Taylor, a former chief of staff at the Department of Homeland Security (DHS), published an essay on the online platform Medium explaining his decision to write the anonymous 2018 essay for the New York Times, as well as a subsequent book titled A Warning.

"I saw Donald Trump prove he is a man without character, and his personal defects have resulted in leadership failures so significant that they can be measured in lost American lives," Taylor wrote.

"So when I left the administration I wrote 'A Warning,' a character study of the current commander in chief and a caution to voters that it wasn’t as bad as it looked inside the Trump administration – it was worse," Taylor continued.

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In the anonymous essay, which drew widespread attention after claiming that its author was a senior administration official, Taylor wrote that some political appointees were actively working to undermine the president's worst impulses.

The essay riled Trump, who ordered his team to begin looking for leakers in the White House.

Taylor served in DHS from 2017 to 2019, including as chief of staff for former DHS secretary Kirstjen Nielsen, who was widely criticized for overseeing a policy at the US southern border that saw immigrant children separated from their parents.

He has been openly critical of the Trump administration while working as a contributor for CNN in the lead up to the November US presidential election.

Trump responded to the news about Taylor's identity by calling him a "low level staffer" and a "sleazebag who has never worked in the White House."

"This guy, in my opinion, he should be prosecuted," Trump said during a rally in Arizona.

White House press secretary Kayleigh McEnany, meanwhile, said Taylor's actions are "everything people hate about Washington."

Some analysts were also critical of the New York Times for characterizing Taylor as a senior administration official, arguing that his role at DHS was not senior enough to warrant the description.