(CNN) House Democratic leaders announced Tuesday they will bring two articles of impeachment against President Donald Trump , charging him with abuse of power and obstruction of Congress to set in motion the third impeachment of a US president in history.

The announcement of impeachment articles marks the culmination of an intense, fast-moving investigation into the President's dealings with Ukraine and represents a historic choice for lawmakers with less than a year before the next election.

The six House Democratic chairs who have led the investigations against the President this year unveiled the impeachment articles on Tuesday morning with House Speaker Nancy Pelosi, and they were formally introduced by House Judiciary Chairman Jerry Nadler.

"Today, in service to our duty to the Constitution and to our country, the House Committee on the Judiciary is introducing two articles of impeachment, charging the President of the United States Donald J. Trump with committing high crimes and misdemeanors," Nadler said.

Democrats charge that Trump abused his office by pressuring Ukraine to investigate his political rivals ahead of the 2020 election while withholding a White House meeting and $400 million in US security aid from Kiev. And they say that Trump then obstructed the investigation into his misconduct with a blanket blockade of subpoenas and refusing to allow key senior officials to testify before Congress.

Tuesday's introduction sets the stage for a dramatic impeachment vote on the House floor next week, after the House Judiciary Committee debates and approves the articles beginning on Thursday.

House Intelligence Chairman Adam Schiff said the evidence against Trump was "overwhelming and uncontested," and argued Democrats cannot wait for the judicial branch to rule on the witnesses and documents the Trump administration is blocking from Congress.

"The argument why don't you just wait amounts to this: why don't you just let him cheat in one more election?" said Schiff, a Democrat from California. "Despite everything we have uncovered, the President's misconduct continues to this day, unapologetically and right now."

The White House slammed the introduction of the impeachment articles and said Trump would "address these false charges in the Senate" after the President did not participate in the House proceedings.

"The announcement of two baseless articles of impeachment does not hurt the President, it hurts the American people, who expect their elected officials to work on their behalf to strengthen our nation," White House press secretary Stephanie Grisham said in a statement. "The President will address these false charges in the Senate and expects to be fully exonerated, because he did nothing wrong."

Senate Majority Leader Mitch McConnell said the Senate trial will start "right around the time the bowl games end," at a press briefing following Senate lunches Tuesday. An aide told CNN that McConnell was referring to the January 1 college football games and not the national championship game on January 13.

This is the fourth time a US president is staring down the serious prospect of impeachment. The House voted to impeach Presidents Andrew Johnson and Bill Clinton, who were both acquitted by the Senate, while President Richard Nixon resigned before impeachment articles went to the House floor.

The announcement of impeachment articles from Pelosi came just minutes before the speaker then announced a deal Tuesday to advance President Donald Trump's renegotiated North American Free Trade Agreement — handing the President a victory at the same time Democrats are moving to impeach him.

The two articles are included in a nine-page resolution accusing Trump of unprecedented misconduct and calling for his removal from office.

"Donald J. Trump has abused the powers of the Presidency, in that: Using the powers of his high office, President Trump solicited the interference of a foreign government, Ukraine, in the 2020 United States presidential election," the first article says. "Wherefore President Trump, by such conduct, has demonstrated that he will remain a threat to national security and the Constitution if allowed to remain in office, has acted in a manner grossly incompatible with self-governance and the rule of law."

The article on obstruction of Congress charged that Trump "directed the unprecedented, categorical and indiscriminate defiance of subpoenas issued by the House of Representatives pursuant to its 'sole power of impeachment.' "

"In the history of the Republic, no President has ever ordered the complete defiance of an impeachment inquiry or sought to obstruct and impede so comprehensively the ability of the House of Representatives to investigate 'high crimes and misdemeanors,'" the Democrats wrote.

The introduction of articles of impeachment comes after a two-month investigation into Ukraine that was sparked by an anonymous whistleblower complaint alleging Trump solicited election help from Ukraine on a July 25 phone call with Ukrainian President Volodymyr Zelensky. The 17 witnesses who testified during the House impeachment inquiry described a broader effort in Ukraine in which the President directed his personal attorney Rudy Giuliani to push Ukraine to investigate former Vice President Joe Biden and the 2016 election.

Following the investigation led by the House Intelligence Committee, which included public hearings with 12 witnesses, the House Judiciary Committee held two hearings laying out the case for impeachment and the evidence against the President.

The impeachment vote is likely to split largely along party lines, with a handful of potential Democratic defections. No Republicans appear likely to vote to impeach the President after an investigation congressional Republicans denounced as unfair and biased against the President.

"It is not difficult to defend this President because this President did nothing that is impeachable," said House Minority Leader Kevin McCarthy, a California Republican. "This is not a day that America will be proud about."

Democrats had debated adding a third article of impeachment on obstruction of justice, which would have captured the allegations against Trump that were detailed in former special counsel Robert Mueller's investigation.

Pelosi and her top lieutenants ultimately decided to keep the articles focused narrowly on Ukraine, out of concern for moderates who only backed an impeachment inquiry once the Ukraine scandal spilled into public view.

House Foreign Affairs Chairman Engel told reporters that adding an obstruction of justice charge to the impeachment articles would be a "mixed bag of tricks," and that it didn't have broad consensus in the caucus — meaning it could be tough to get the votes to pass.

Still, Judiciary Committee Democrats said the episodes detailed in the Mueller report were reflected in the articles to show how Trump's actions in Ukraine were part of a broader pattern of misconduct that began during the 2016 election and still continues today. Mueller was not mentioned explicitly, however.

"These actions were consistent with President Trump's previous efforts to undermine United States government investigations into foreign interference in United States elections," Democrats wrote in the obstruction of Congress article.

Judiciary members said that the abuse of power charge was so all-encompassing that it covered all of Trump's behavior.

"The pattern of conduct of asking a foreign government to cheat certainly will be reflected, and his pattern of obstruction also will be part of the case that we make," said Rep. Eric Swalwell, a California Democrat on both the Judiciary and Intelligence Committees. "This is just what he does when he gets caught."

Rep. Pramila Jayapal of Washington, a Democrat on the Judiciary panel, said that the conduct Mueller documented was "terrible" but that Ukraine was "even more egregious because he's sitting here and continuing to do it."

"We want to give the Senate the strongest possible case that they can have while he's in the White House abusing his power, inviting a foreign ally to interfere in our elections, but not the first time," she said.

This story has been updated with additional developments Tuesday.