Exactly what was said in the phone call is unclear, but according to CNN, which cites two sources of transparency in the conversation, Donald Trump should have talked about Biden's intentions in Ukraine. Trump should also have promised to remain silent about the protests in Hong Kong as long as US-China trade talks were ongoing.

According to the data, the calls should be stored on the same high-grade security server as the telephone calls between Trump and Ukrainian President Volodmyr Zelensky.

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Trump: "I think Biden will go there" Photo: TT

The White House denies conversation

When CNN asked the White House earlier this week about the calls, they did not deny that they had taken place.

- World leaders must be able to speak freely with the President - it is a key component of effective diplomacy. And that's why such conversations are kept confidential, said White House press secretary Stephanie Grisham.

- We will not begin to discuss the content of every conversation President Trump has with world leaders, other than to say that the conversations have always been accurate.

Want to review China trip

On Thursday, Donald Trump in front of cameras urged China to investigate Democratic presidential candidate Joe Biden and his son Hunter Biden for cheating in China. Hunter Biden has been involved in a Ukrainian company against which corruption allegations have been made.

The basis for Trump's statement is said to be a trip that Joe and Hunter Biden made in 2013, when Joe Biden was vice president. During a visit to China, Hunter Biden should have met Chinese bank officials to open a fund, NBC News writes.