(Adds comments by Trump in Fox News interview and at rally)
By Susan Heavey and Makini Brice
WASHINGTON, Sept 6 (Reuters) - Senior aides to Donald Trump scrambled on Thursday to disown a New York Times column written by an unnamed administration official that slammed the leadership style of the U.S. president as impetuous, petty and ineffective.
The unsigned opinion piece, derided by Trump as "gutless", drew disavowals from at least 11 top advisers to the president, including Vice President Mike Pence, Ambassador to Russia Jon Huntsman, Secretary of State Mike Pompeo and Defense Secretary James Mattis, all of whom denied any responsibility for its authorship.
Trump seethed about the piece and framed it as a jab from critics in denial about his successes, while Washington was consumed with speculation about who wrote it.
"I don't mind when they write books and they write lies because they get discredited," Trump said in an interview with Fox News Channel, set to air on Friday, that was taped ahead of a rally on Thursday in Billings, Montana.
But in this instance, he said, the author could not be discredited because the piece was published anonymously.
"Is it subversion? Is it treason? It's a horrible thing," he later told supporters during the rally.
Published on Wednesday, the column appeared days after the release of excerpts from a book by famed reporter Bob Woodward that portrayed Trump as prone to impulsive decision-making. The excerpts said aides sometimes tried to limit what they saw as damaging behavior by disregarding his instructions.
The Times op-ed, and Woodward's book, which is to be published next week, followed many news articles during Trump's 19-month presidency that have depicted turbulence inside the White House under his leadership.
The former New York businessman and reality TV star has had an unusually high level of staff turnover and has sometimes publicly criticized his top aides.
The critical spotlight on Trump's leadership comes two months before elections in which his fellow Republicans will try to hold their majorities in both chambers of Congress. The November vote will be widely seen as a referendum on Trump.
SECRET 'DEEP STATE' AGENDAS
The Times opinion section said the piece was written by a senior official in the administration and that it was taking the rare step of publishing an anonymous article because disclosing the author's identity would jeopardize the person's job.
"Unelected deep state operatives who defy the voters to push their own secret agendas are truly a threat to democracy itself," Trump told the Montana rally.