President Donald Trump's brother Robert Trump filed a petition in Queens County Surrogate's Court Wednesday seeking a temporary restraining order against the brothers' niece, Mary Trump, and Simon & Schuster, the publisher of Mary Trump's upcoming book about the president.

Charles Harder, who is representing Robert Trump, argued that Mary Trump is subject to a confidentiality provision in the 2001 settlement agreement associated with her grandfather Fred Trump's will.

"The court cases involving Fred Trump's will had received extensive publicity and the family made a decision collectively to enter into an agreement that would maintain the confidentiality of the family's private matters," Harder wrote.

Under the confidentiality agreement, family members, including Mary Trump, agreed not to publish accounts of "their litigation or relationship[s]" unless they obtained consent from Robert Trump, Donald Trump, then-Judge Maryanne Trump Barry of the U.S. Court of Appeals for the Third Circuit and the directors and officers of two companies, Harder wrote.

Mary Trump's book, "Too Much and Never Enough: How My Family Created the World's Most Dangerous Man," is set to be published July 28, according to the Simon & Schuster website.

While Robert Trump has not reviewed the content of the book, Harder argued that public statements by Mary Trump and the publisher have shown the book will contain information about her relationships that are protected under the confidentiality agreement.

Queens County Surrogate's Court reserves jurisdiction over the settlement agreement and its terms, according to the petition.

Gibson, Dunn & Crutcher partner Theodore Boutrous Jr., who is representing Mary Trump, issued a statement Tuesday.

"President Trump and his siblings seek to suppress a book that will discuss matters of utmost public importance," he said. "They are pursuing this unlawful prior restraint because they do not want the public to know the truth. The courts will not tolerate this brazen violation of the First Amendment."

Harder and Simon & Schuster did not immediately respond to requests for comment Wednesday.

The filing comes just a week after the civil division of the U.S. Department of Justice sued former national security adviser John Bolton to try to stop the publication of a memoir about his time in the White House.

In that case, U.S. District Judge Royce Lamberth of the District of Columbia questioned his own ability to block the publication at a hearing, noting that Bolton's memoir had already been printed and distributed widely to bookstores, reviewers and reporters in the final days before its planned release to the public.

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