House Speaker Nancy Pelosi announces formal impeachment inquiry of Trump, says his actions were a ‘betrayal of national security.’

“The actions of the Trump presidency have revealed the dishonorable fact of the president’s betrayal of his oath of office, betrayal of our national security and betrayal of the integrity of our elections,” Pelosi said in brief remarks. “Therefore, today, I am announcing the House of Representatives is moving forward with an official impeachment inquiry.”

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The push for impeachment comes as the White House faces heightened scrutiny over a July phone call between Trump and Ukrainian President Volodymyr Zelensky. An apparent “whistleblower,” who, according to reports, has no firsthand knowledge of the conversation, has submitted a formal complaint accusing the president of requesting that the foreign leader investigate 2020 Democratic front-runner and former Vice President Joe Biden and his son Hunter Biden over their business dealings with a Ukrainian energy company.

The intelligence inspector general deemed the complaint credible and urgent, but officials at the Department of National Intelligence have come to a different conclusion and have not released the report to Congress.

Ahead of Pelosi’s announcement, Trump authorized the release of a transcript of his call with Ukraine’s president. The transcript is to be made public on Wednesday.

The president immediately lashed out on Twitter:

According to this: Impeachment is a rare and extraordinary first step that could lead to overturning the decision of U.S. voters in 2016 to elect Trump. Pelosi’s decision foreshadows an intensely partisan fall, triggering pushback from Trump allies with repercussions for the 2020 campaign.

Impeachment has only occurred twice in U.S. history — against Presidents Andrew Johnson and Bill Clinton. Neither man was removed from office. President Richard M. Nixon resigned in 1974 rather than face a House vote on impeachment.