Democratic presidential candidate Joe Biden said President Donald Trump is trying to make Ukraine investigate him because he knows Biden will “beat him like a drum.”

He spoke to reporters Saturday, after the revelation of Trump’s phone call with the Ukrainian president where he allegedly pressured the president to investigate Joe Biden “about eight times.”

Biden expressed disgust with Trump’s alleged phone call.

“He is violating every basic norm of a president,” Biden told a reporter. “You should be asking him the question: why is he on the phone with a foreign leader, trying to intimidate a foreign leader?”

He then echoed the thoughts of several House democrats, calling the offense potentially impeachable.

“Depending on what the House finds he could be impeached, but I’m not making that judgement now,” said Biden. “The House should investigate it.This appears to be an overwhelming abuse of power.”

Biden has been under fire for threatening to withhold a billion dollars of U.S. aid from Ukraine during the Obama administration, unless the government fired their top prosecutor. That same prosecutor was investigating Burisma Holdings, a gas company that his son worked for.

Trump allegedly pushed for an investigation into corruption charges based on this supposed conflict of interest. His personal attorney Rudy Giuliani admitted to CNN’s Chris Cuomo that he asked a Ukrainian official about Biden.

“The only thing I asked about Joe Biden is to get to the bottom of how it was that Lutsenko, was appointed, dismissed the case,” Giuliani said, referring to former Ukrainian prosecutor General Yuriy Lutsenko.

“So you did ask Ukraine to look into Joe Biden,” Cuomo followed up.

“Of course I did,” said Giuliani.

Congresswoman Alexandria Ocasio-Cortez (D-New York) is among several Democrats calling for Trump’s impeachment, based on the phone call scandal.

“At this point, the bigger national scandal isn’t the president’s lawbreaking behavior – it is the Democratic Party’s refusal to impeach him for it,” she tweeted Sunday.

Democratic presidential candidate Elizabeth Warren also criticized Congress’ reluctance to begin the impeachment process, tweeting that “By failing to act, Congress is complicit in Trump’s latest attempt to solicit foreign interference to aid him in US elections.”