Trump calls for China to investigate Bidens; former Ukraine envoy testifies on Capitol Hill

President Donald Trump on Thursday called on both Ukraine and China to investigate former vice president Joe Biden and his son Hunter in relation to the younger Biden's business dealings during the tenure of the former vice president.

His comments came as Kurt Volker, who resigned last week as the Trump administration's special envoy for Ukraine, was being interviewed behind closed doors in front of three House committees, accelerating the Democratic-led impeachment inquiry.

Volker was among the officials mentioned by name in the whistleblower report raising concerns about Trump's July phone call in which Trump pressed Ukrainian President Volodymyr Zelensky to investigate former vice president Joe Biden and his son.

In a television interview that aired earlier, House Speaker Nancy Pelosi, D-Calif., accused her Republican colleagues of being loyal to President Trump and not the Constitution.

Trump suggested Thursday that another foreign country should investigate Biden and his son Hunter, even though House Democrats have launched an impeachment inquiry against him over his request that the Ukrainian president do the same.

President Donald Trump told media China should start an investigation into the Bidens. Photo / AP

Biden is a 2020 presidential candidate.

"China should start an investigation into the Bidens, because what happened in China is just about as bad as what happened with Ukraine," Trump told reporters.

Trump's allegations regarding Hunter Biden and China centre on the younger Biden joining the board of an investment firm whose partners included Chinese entities while his father was vice president. The president and his allies have provided no evidence to back up their claims of wrongdoing.

Trump made his comments to reporters as he prepared to depart the White House.

Asked what he wanted from Zelensky, Trump said, "If they were honest about it, they would start a major investigation into the Bidens."

Former Vice President and Democratic presidential candidate Joe Biden. Photo / AP

Trump added: "Likewise, China should start an investigation into the Bidens."

Asked whether he had requested Chinese President Xi Jinping to help investigate the Bidens, Trump replied: "I haven't, but it's certainly something we should start thinking about."

Trump also told reporters he had fired former U.S. ambassador to Ukraine Marie Yovanovitch because he "heard very bad things about her."

Yovanovitch was recalled from her position in Ukraine this year amid a flurry of political attacks by conservative media and other allies of Trump, including Trump lawyer Rudy Giuliani, who targeted her with unsubstantiated accusations and argued that she "should be part of the investigation as part of the collusion."

Yovanovitch is scheduled to appear before three House committees on Oct. 11 as part of the impeachment inquiry.

As Volker was scheduled to begin his deposition, Giuliani took to Twitter to accuse the Democratic-led committees of conducting a "Star Chamber" and shared a text exchange with Volker.

Kurt Volker, a former special envoy to Ukraine, arrives for a closed-door interview with House investigators. Photo / AP

In his tweet, Giuliani echoed complaints of Republican lawmakers about their more limited role in the proceedings.

"This is a Star Chamber, illicit and part of their conspiracy to violate constitutional rights condoned by their media lamb dogs," Giuliani added. "Kurt did nothing wrong."

He included a text exchange with Volker in which Volker asked Giuliani if he were "back stateside" and suggested they "get together."

In subsequent tweets, Giuliani shared other text messages about arranging meetings.

On Thursday, the committees are expected to examine Volker's role in facilitating contacts between Giuliani and officials of the Ukrainian government in the summer.

Pelosi accused Republicans of being loyal to Trump and not the Constitution during a television interview that aired Thursday in which she discussed the impeachment inquiry.

Speaking to ABC News, she derided her GOP colleagues for attacks on the inquiry that she launched last week.

"When I took the oath of office to support and defend the Constitution, as my colleagues have done as well, I did not say I will do this as long as the Republicans can understand the Constitution," Pelosi said. "So the fact that their loyalty is to Trump and not to the Constitution is not going to slow down or impair our ability to keep the republic."

During the interview with ABC's George Stephanopoulos, Pelosi also pushed back on a Republican argument that Trump's call with Zelensky was not problematic because there was no explicit "quid pro quo" between providing US military aid to Ukraine and investigating the Bidens.

Trump's call in which he asked Zelensky for a "favour" came shortly after the Trump administration suspended congressionally approved aid.

"First of all, it's not necessary," Pelosi said of a "quid pro quo."