President Donald Trump's successive scandals were not the first in the history of US presidencies, preceded by several presidents.

Who does not mention former President Bill Clinton's emotional scandal with White House intern Monica Lewinsky, where Clinton was held accountable by Congress and summoned for an interrogation session that almost toppled him.

The Watergate scandal was the most famous in America's history, with former president Richard Nixon's decision to spy on the offices of the rival Democratic Party in the Watergate building. The move triggered a massive political crisis that led to the resignation and trial of the president in 1974.

Now the United States is close to a new Watergate scandal.

From a seemingly normal telephone conversation between US President Donald Trump and his Ukrainian counterpart, Volodymyr Zelinsky, to launch an investigation by Democrats seeking to isolate the White House master.

The following is a reminder of the main facts that made a telephone conversation between Trump and his Ukrainian counterpart a political scandal.

July 25: A few days after he suspends hundreds of millions of dollars in military aid to Ukraine, Trump made a phone call to his counterpart Volodymyr Zelinsky.
The two men talked about "ways to strengthen relations between the United States and Ukraine," according to the White House.

- August 12: A US intelligence informant issues a Ukraine-centered telephone call, saying it is related to an "emergency problem."
Intelligence Inspector General Michael Atkinson has seen the document as "credible" and forwarded it to US intelligence chief Joseph Maguire to send it to Congress.
After consulting with the White House and the Justice Department, Maguire concluded that he had no obligation to do so. Atkinson then decided to take care of himself and notify Congress directly of the existence of the communication without disclosing its contents.

- September 18: The case quickly took on a new dimension the same evening
President Trump's contacts with a foreign president. She added that this talk «included a promise of concern» laboratory. The following day, The Washington Post and The New York Times published articles revealing that the conversation took place between Trump and the Ukrainian president.

- September 24: Democratic Speaker of the House of Representatives Nancy Pelosi announced the launch of an investigation in an attempt to isolate the president, after she had so far refused to resort to this mechanism, which Trump condemns.

September 25 - The White House publishes excerpts of the phone call that prove Trump has already asked Zelinski to investigate Joe Biden. The Democrats denounced the pressure they considered certain to have been applied to the Ukrainian president.
But Trump replied: “Isolated because of what? It's a joke".

- September 26: The content of the letter, which accuses the US president of "asking for interference" from Ukraine in the campaign for re-election in 2020, was published.
The Democratic opposition cited the document to accuse the White House of seeking to "strangle the scandal."

September 27: Democratic lawmakers send an official memo to Secretary of State Mike Pompeo, who was present during Trump's contact with Zelensky in July, asking him to hand them the documents necessary for their investigation.

- October 1: Pompeo, accusing the Democrats in Congress of "trying to intimidate" and denouncing "deep legal weaknesses" in what they are doing.
Trump has demanded the arrest of Adam Schiff, the deputy supervising the investigation, for "treason."

October 3: In response to the campaign, Trump called on China to investigate Joe Biden in parallel with congressional hearing of Kurt Volcker in closed session.
Democrats published text messages dating back to July showing that US diplomacy had asked the Ukrainian president to investigate Biden and his son Hunter in exchange for a meeting between Trump and Zelinsky at the White House.