Ukrainian President Volodymyr Zelenskiy indicated to President Donald Trump that his government is willing to open a "joint investigative committee" to probe former Vice President Joe Biden and allegations of corruption.

According to Kyodo News, Zelenskiy said the offer is contingent on the U.S. opening an investigation into Biden and asking the Ukrainians for assistance.

That investigation would have to be "based on international law, in accordance with domestic laws," Kyodo summarized Zelenskiy as saying.

Trump and Zelenskiy spoke on the phone in July, the transcript of which has become highly controversial. Trump is accused of issuing the threat of not providing U.S. aid to Ukraine unless that country investigated both the 2016 U.S. election interference and Biden.

Biden has come under scrutiny for helping his son Hunter get a job working for a Ukrainian energy company and forcing Ukraine to fire a prosecutor who had been investigating the arrangement.

House Democrats opened an impeachment inquiry of Trump after a whistleblower came forward with concerns about the July phone call between the two leaders. A second whistleblower has since emerged.

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