KIEV (Sputnik) - Ukrainian investigators have not questioned former US Vice President Joe Biden or his son Hunter as part of an investigation into the Burisma Group's activity, Nazar Kholodnitskiy, head of the Specialized Anti-Corruption Prosecutor's Office of Ukraine, said.

"As of now, Bidens have not been questioned or summoned as part of these proceedings, neither father nor son", Kholodnitskiy said on the air of the Novoye Vremya radio.

He said that on August 1, 2017, the prosecutor had decided to close the case, in particular, because the case had been unsuccessfully investigated for about two years.

“Unfortunately, then the investigation, the detectives were unable to provide any evidence so that this case could have any further completion. The last meeting was in May 2017, where it was noted that nothing was being done in the case, and the prosecutors gave the detectives two more months of the deadline in order to either show the result, or the case will be closed. On August 1 the proceedings supervisor made this decision", the official said.

The statement comes amid a growing scandal around US President Donald Trump after a US government whistleblower claimed the president had pressured Zelensky during a July phone call to look into a case that could potentially tarnish the political image of his main Democratic opponent, Joe Biden, in the 2020 presidential race. On 25 September, the White House unclassified an unredacted transcript of the conversation in question, which confirmed that Zelensky had promised Trump to look into the Biden case.

Last week, US media reported, citing a whistleblower’s complaint, that during the July phone call Trump urged Zelensky to cooperate in a probe into the business dealings of Joe Biden’s son, Hunter Biden, with a Ukrainian gas company. In 2016, the ex-US vice president publicly admitted to having threatened Ukrainian authorities with pulling $1 billion in US loan guarantees if Kiev did not fire the prosecutor in charge of the case against his son.