RNA - Speaking to reporters on Tuesday, Nadler said Trump abused his power by pressuring Ukraine and that he has "declared himself above accountability", RT reported.
"No one, not even the president, is above the law," he added.
He stated that the second article of impeachment will be for obstruction of Congress. The Judiciary Committee will meet later this week to consider the articles.
Nadler also claimed that lawmakers must "act now" because the integrity of the 2020 elections are "at stake".
In a statement following the unveiling of the charges, Trump's 2020 campaign manager Brad Parscale said impeachment was "too divisive" and Americans "don't agree with this rank partisanship". The Democrats, he added, are "putting on this political theater because they don't have a viable candidate for 2020 and they know it".
Trump is now officially the fourth US president to face impeachment and, if impeached, would be the third to face a trial in the Senate.
Democrats launched impeachment proceedings on the back of whistleblower claims that Trump had tried to pressure Ukrainian President Volodymyr Zelensky to open a corruption probe into a gas company employing former VP Joe Biden’s son, Hunter. They claim that Trump offered Zelensky a quid pro quo, offering military aid in return for an investigation which could hurt Biden politically during the 2020 presidential campaign.
The first White House official to respond to the introduction of impeachment articles, Acting Chief of Staff Mick Mulvaney told The Wall Street Journal that the impeachment inquiry was a "political process, not a legal process."
On Twitter, Trump himself hit back, saying that the notion that he pressured Ukraine was "ridiculous" and that Nadler "knows that is not true".
Republicans believe the impeachment inquiry is a political witch hunt against the president and say that Democrats have so far produced no solid proof of any wrongdoing by Trump.