She said Democrats, "have plenty of questions for Mr. Giuliani", reported Bloomberg. "Given the apparent depth of his involvement in the president's effort to convince foreign governments to investigate a political rival, he must testify under oath".
Giuliani, the former mayor of NY, has emerged as a central figure in the Democratic-led impeachment inquiry into Trump.
After Energy Secretary Rick Perry, U.S. Ambassador to the European Union Gordon Sondland and the then-U.S. special envoy to Ukraine Kurt Volker returned from Zelensky's inauguration, the trio hoped to sit-down with Trump to express their belief that he should meet with Zelensky.
Giuliani is one of the central figures at the center of the current impeachment inquiry.
Graham, a Republican from SC, said, "It is time for the Senate to inquire about corruption and other improprieties involving Ukraine", noting that his invitation was for Giuliani to "come before the Senate Judiciary Committee to inform the Committee of his concerns".More news: Fitness Facts: Breast cancer awareness
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Trump has echoed Giuliani's allegations about Biden and raised the issue in a July 25 phone call with Ukraine's new president Volodymyr Zelensky - a discussion that occurred amid Giuliani's pressure campaign and at a time the White House had quietly placed a hold on military assistance to Ukraine, which was eventually released after news of the hold became public.
For the last few weeks, most of Giuliani's claims of wrongdoing against Biden revolved around the ex-veep's role in the firing of Ukrainian ex-prosecutor Viktor Shokin. But there has been no evidence Hunter Biden was ever under investigation, and a variety of western bodies also wanted the former prosecutor to go for failing to root out corruption in Ukraine.
US officials, the whistleblower wrote, were "deeply concerned" by Giuliani's communications with Ukraine. Trump would likely have to waive attorney-client privilege in order for Giuliani to testify before Congress, and it appears unlikely that he will do so. Two other Democratic presidential hopefuls also sit on the committee: Cory Booker and Amy Klobuchar. A campaign spokesman told Bloomberg that "bringing forward noted conspiracist and liar Rudy Giuliani would further discredit the reputation of the Senate Judiciary Committee under Senator Graham".
Shortly after Graham invited Giuliani to appear before the panel, Harris, a former prosecutor, applauded the move.