(CNN) California Sen. Kamala Harris said Thursday she wants the White House to release information related to President Donald Trump's previous conversations with Chinese President Xi Jinping, following Trump's public call for China to investigate Joe Biden and his son.

"I'm calling on the White House to actually release whatever transcripts, whatever recordings, whatever notes there are about Donald Trump's previous conversations with Xi, because we need to know what he has now said in private conversations," Harris told CNN's Jake Tapper on "The Lead."

"Clearly he doesn't get it," Harris said of Trump. The senator said the President "should not be in the business of working with foreign leaders against our democracy. It is a violation of the oath."

Harris's comments came hours after Trump said he wants both Ukraine and China to investigate Biden and his son, Hunter. There is no evidence of wrongdoing by Joe or Hunter Biden in Ukraine. There's also no evidence that the former vice president received any money from China and a lawyer for Hunter Biden pushed back on this characterization calling it "a gross misrepresentation."

Also on Thursday, Harris, whose campaign has been unable to sustain the momentum Harris sparked with her first debate performance in June, brushed off the results of a new poll that saw her slide from a front-runner position in her home state to single digits in a survey of likely voters in California. "The only poll that matters is on election night," Harris said.

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