Asked about the current impeachment effort against President Donald Trump, Biden criticized the president for holding up aid to Ukraine while people in the country "are getting killed by Russian soldiers".

He furthermore said it was a "conspiracy theory" that Biden was corrupt in his dealings with Ukraine while serving as vice president. If the corruption had involved somebody named Natty Bumpo, and Trump asked Zelensky to look into it, nobody would have had a second thought about it.

"Are you aware that during the Obama administration the US partnered with the United Kingdom and Ukraine on an investigation into the owner of Burisma as part of Ukraine's anti-corruption efforts?" she asked.

He recalled that Trump asked about "the investigation", and that Sondland confirmed that Zelensky would do an investigation. Both Volker and Sondland have cited episodes they failed to mention initially in their closed-door testimony, saying other witnesses had jogged their memory.

Breaking ranks with Trump and the Republican Party in public impeachment testimony, Gordon Sondland, the ambassador to Europe, testified that "the answer is yes" to the question "Was there a "quid pro quo?"

Volker drew a distinction between an investigation into the Burisma Group, which he said would be "appropriate and unremarkable", and into the Bidens, which he said would be "unacceptable".

After the Prosecutor's Office loses investigative functions, these cases, in accordance with their jurisdiction, will be transferred to the National Anti-Corruption Bureau of Ukraine (NABU), the National Bureau of Investigation, and the Security Service of Ukraine (SBU), he said.

"The member of my staff could hear President Trump on the phone asking Ambassador Sondland about 'the investigations.' Ambassador Sondland told President Trump that the Ukrainians were ready to move forward".

Since then, a parade of witnesses has testified publicly and privately about what they recalled about the July 25 phone call between Trump and Ukraine's new leader, Volodymyr Zelenskiy.

She also criticized Schiff for refusing to allow Republicans on the committee to call Hunter Biden as a witness.

Republican lawmakers have noted that Ukraine has received greater military aid under the Trump administration than it did when President Barack Obama was in office. He also said Trump never told him he would block assistance to Ukraine if the investigations he sought weren't undertaken and never told him that conditions were placed on the money.

Graham said the phone calls coincided with the time frame in which a Ukrainian prosecutor, once praised for going after the head of natural gas company Burisma Holdings - a person Graham said was known as the "dirtiest guy in Ukraine" by one top American official - was sacked.

But they gave the administration the benefit of the doubt on other aspects of Ukraine policy the Democrats asked them about, such as whether the partial transcript of the call that the White House eventually released was handled improperly. "That's pretty clear", the 2020 Democrat presidential candidate said during his opening remarks at the Democrat debate in Atlanta, Georgia, hosted by MSNBC and the Washington Post.