RNA - Trump made the remarks on Tuesday after the long-anticipated formal impeachment against him was announced by the Democrat-led House of Representatives.
In the the two articles of impeachment, House Democrats accused the Republican president of abuse of power and obstruction of Congress.
“We must be clear: No one, not even the president, is above the law,” said House Judiciary Committee Chairman Jerrold Nadler at a news conference where he was flanked by House Speaker Nancy Pelosi and other House leaders.
The heart of the issue is whether Trump abused his power by pressuring Ukraine to investigate former vice president Joe Biden, a political rival seeking the Democratic nomination to face Trump in the 2020 election, and then obstructed Congress' investigation into the scandal.
Trump denies having done anything wrong and has called the impeachment probe a hoax.
Addressing supporters in Pennsylvania on Tuesday, the president once again denounced the impeachment process as a "witch hunt."
He also said Pelosi sought to use the US-Mexico-Canada Agreement (USMCA) trade pact to deflect attention from the impeachment effort.
“They announced the impeachment and then an hour later she announced that she is going to do USMCA. You know why, it’s a huge deal and it plays down the impeachment because they’re embarrassed by the impeachment,” Trump told the crowd.
"The silver lining of impeachment and this witch hunt is it's the reason they approved USMCA," Trump said. "Our poll numbers have gone through the roof because of her stupid impeachment."
The US, Mexico and Canada finalized a trade deal on Tuesday that will replace the 25-year-old North American Free Trade Agreement (Nafta).
Representatives from the three countries signed the pact in Mexico. Both Pelosi and Trump, who accused the Democrats of holding up the deal, said they would support the agreement, which now needs approval by legislatures in the three countries before it can move forward.