John Bolton, a former U.S. national security adviser, is set to release a tell-all book that may include highly classified information, including details on President Donald Trump's impeachment.

According to the New York Times, Bolton's memoir will cover his 18-month tenure at the White House and include his assessment of the president. News reports follow the administration's month-long campaign to stop the book's release.

The book has undergone a lengthy review by the National Security Council (NSC), and will allegedly reveal that Trump's connections with Ukraine were not his only "international misconduct." The USA Today reports that Bolton's memoir will tackle the "impeachment malpractice" committed by the House.

Trump's Response

President Trump said the former national security adviser could face criminal charges if he pushed forward with publishing the memoir which is slated to be released on June 23.

In a roundtable meeting at the White House, President Trump accused Bolton of not completing a pre-publication review to ensure that no classified material was included in the memoir.

Attorney General William Barr echoed Trump's accusation, claiming Bolton did not go through a clearance process before publishing sensitive information he accessed during his employment at the White House.

His statement contradicts the claims of Bolton's attorney, Chuck Cooper, who said they spent months working with classification specialists to omit classified material.

Cooper claimed he sent the book's manuscript to classification specialist Ellen Knight by the end of 2019. Knight and Bolton spent four months going through the book multiple times, the lawyer said, as reported by the Associated Press.

Ukraine Controversy

In early September 2019, an anonymous whistleblower accused Trump of using his powers to coerce Ukrainian President Volodymyr Zelensky to interfere in the 2020 U.S. elections, BBC reported.

The complaint, which has since been publicly released, claims the U.S. president used a June 25 call to pressure the Ukrainian government to investigate and uncover damaging information on his political rival, former Vice President Joe Biden and his son, Hunter. The call allegedly came after the administration withheld the foreign country's nearly $400 million military-aid package. A senior official corroborated the whistleblower's claims which the White House has denied.

The issue has been widely debated, with some claiming that soliciting the help of a foreign country to research the opposition constituted an impeachable offence.

The Democrats launched a formal inquiry where multiple officials testified under oath. Rudy Giuliani, the president's personal lawyer, and Secretary of State Mike Pompeo received subpoenas.

Gordon Sondland, the U.S. Ambassador to the European Union, told Congress he was working with the guidance of the president to put pressure on Ukraine to investigate the Bidens. He also revealed the administration has added a conditional offer of an official White House visit for Ukraine's president if it publicly announced a probe.

In December, Democratic leaders charged the president with abuse of power and obstruction of Congress. A week before Christmas, the House voted to impeach Trump.

The president was cleared following a two-week trial held by the Senate in January and February 2020.

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