By ZEKE MILLER and CATHERINE LUCEY
Associated Press

WASHINGTON (AP) - An opinion piece in The New York Times by an anonymous senior administration official claiming to be part of a "resistance" working "from within" to thwart President Donald Trump's "worst inclinations" set off a wild guessing game inside and outside the White House on the author's identity.

In an extraordinary move, a furious Trump tweeted a demand Wednesday night that if "the GUTLESS anonymous person does indeed exist, the Times must, for National Security purposes, turn him/her over to government at once!" White House press secretary Sarah Huckabee Sanders called on the "coward" who wrote the piece to "do the right thing and resign."

White House officials did not immediately respond to a request to elaborate on Trump's call for the writer to be turned over to the government or the unsupported national security ground of his demand.

To some, the ultimatum appeared to play into the very concerns about the president's impulses raised by the essay's author. Trump has demanded that aides identify the leaker, according to two people familiar with the matter, though it was not yet clear how they might go about doing so. The two were not authorized to speak publicly and spoke on condition of anonymity.

A "House of Cards"-style plot twist in an already over-the-top administration, Trump allies and political insiders scrambled to unmask the writer.

The author, claiming to be part of the "resistance" to Trump "working diligently from within" his administration, said, "Many Trump appointees have vowed to do what we can to preserve our democratic institutions while thwarting Mr. Trump's more misguided impulses until he is out of office."

"It may be cold comfort in this chaotic era, but Americans should know that there are adults in the room," the author continued. "We fully recognize what is happening. And we are trying to do what's right even when Donald Trump won't."

The text of the op-ed was pulled apart for clues: The writer is identified as an "administration official"; does that mean a person who works outside the White House? The references to Russia and the late Sen. John McCain - do they suggest someone working in national security? Does the writing style sound like someone who worked at a think tank? In a tweet, the Times used the pronoun "he" to refer to the writer; does that rule out all women?

The newspaper later said the tweet referring to "he" had been "drafted by someone who is not aware of the author's identity, including the gender, so the use of 'he' was an error."

Hotly debated on Twitter was the author's use of the word "lodestar," which pops up frequently in speeches by Vice President Mike Pence. Could the anonymous figure be someone in Pence's orbit? Others argued that the word "lodestar" could have been included to throw people off.

Trump, appearing at an unrelated event Wednesday at the White House, lashed out at the Times for publishing the op-ed.

"They don't like Donald Trump and I don't like them," he said of the newspaper. The op-ed pages of the newspaper are managed separately from its news department.

In a blistering statement, the press secretary accused the author of choosing to "deceive" the president by remaining in the administration and putting himself or herself "ahead of the will of the American people. The coward should do the right thing and resign."

Sanders also called on the Times to "issue an apology" for publishing the piece, calling it a "pathetic, reckless, and selfish op-ed."

Showing her trademark ability to attract attention, former administration official Omarosa Manigault Newman tweeted that clues about the writer's identity were in her recently released tell-all book, offering a page number: 330. The reality star writes on that page: "many in this silent army are in his party, his administration, and even in his own family."

The anonymous author wrote in the Times that where Trump has had successes, they have come "despite - not because of - the president's leadership style, which is impetuous, adversarial, petty and ineffective."

The assertions in the column were largely in line with complaints about Trump's behavior that have repeatedly been raised by various administration officials, often speaking on condition of anonymity. And they were published a day after the release of details from an explosive new book by longtime journalist Bob Woodward that laid bare concerns among the highest echelon of Trump aides about the president's judgment.

The writer of the Times op-ed said Trump aides are aware of the president's faults and "many of the senior officials in his own administration are working diligently from within to frustrate parts of his agenda and his worst inclinations. I would know. I am one of them."

The writer also alleged "there were early whispers within the cabinet of invoking the 25th Amendment" because of the "instability" witnessed in the president. The 25th Amendment allows the vice president to take over if the commander in chief is "unable to discharge the powers and duties of his office." It requires that the vice president and a majority of the Cabinet back relieving the president.

The writer added: "This isn't the work of the so-called deep state. It's the work of the steady state."

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