Former Vice President Joe Biden, for the first time, called for President Donald Trump's impeachment.

Speaking in Manchester, N.H., Biden said, "Donald Trump has violated his oath of office, betrayed the nation, and committed impeachable acts."

"To preserve our Constitution, our democracy, our basic integrity, he should be impeached," Biden added.

"The United States cannot afford to have a president who will abuse whatever power available to them to get re-elected," Biden said, slamming Trump's request to the Ukrainian government to open an investigation into Biden and his son Hunter Biden.

Trump asked the Ukrainian government in a July 25 phone call with Ukrainian President Volodymyr Zelensky to investigate Biden and probe allegations about Ukraine's role in the 2016 U.S. presidential election. Democrats have cited evidence showing that the U.S. government withheld military aid from Ukraine as part of the effort to pressure Ukraine into opening the investigation.

Trump has accused Biden's son of "corruption" relating to his board seat on a Ukrainian gas company, though Ukrainian prosecutors have said Hunter Biden did not do violate any laws.

And on Oct. 3, Trump urged China to investigate Biden, though the Chinese government has publicly declined to do so.

In his speech today, Biden said there was "no truth in [Trump's] charges against me and my son. Zero."

Previously, Biden had hedged his comments about Trump despite the launching of an impeachment inquiry into Trump.

"If the president does not comply with such a request of the Congress, if he continues to obstruct Congress, and flaunt the law," Biden had said on Sept. 24, "Donald Trump will leave Congress, in my view, no choice but to initiate impeachment."

Shortly after Biden made his remarks, Trump tweeted in response and posted a campaign ad about Bide.

"So pathetic to see Sleepy Joe Biden, who with his son, Hunter, and to the detriment of the American Taxpayer, has ripped off at least two countries for millions of dollars, calling for my impeachment - and I did nothing wrong," Trump wrote.

Biden later responded on Twitter.

"Thanks for watching. Stop stonewalling the Congress. Honor your oath. Respect the Constitution," Biden wrote, also calling on Trump to release his tax returns.

Contributing: Aamer Madhani, Deirdre Shesgreen