KIEVKIEV (Reuters) - Ukraine has widened its investigation into the founder of energy company Burisma to include suspicion of embezzling state funds, Prosecutor General Ruslan Ryaboshapka said on Wednesday.

Allegations of wrongdoing at Burisma go to the heart of a U.S. impeachment inquiry into whether President Donald Trump improperly pressured Ukraine's leadership to investigate his main rival in the 2020 presidential race.

Trump wants Ukraine to launch an investigation into former Vice President Joe Biden and his son Hunter, who was a board member at Burisma from 2014-2019.

ADVERTISEMENT

The prosecutor who has investigated Burisma is Kostiantyn Kulyk, who previously met Trump's personal lawyer Rudy Giuliani to discuss accusations against the Bidens.

After he took office in late August, Ryaboshapka launched a wide-ranging audit of criminal cases to see whether they had been conducted properly. Thirteen of them relate to Burisma founder Mykola Zlochevsky, Ryaboshapka told reporters at a briefing on Wednesday.

Burisma did not respond to a request for comment.

Ryaboshapka's predecessors oversaw a series of investigations into Zlochevsky, a multimillionaire former minister of ecology and natural resources. The allegations concern tax violations, money-laundering and licences given to Burisma during the period where Zlochevsky was a minister.

Ryaboshapka said Zlochevsky was now suspected of the "theft of government funds on an especially large scale," but did not provide evidence or details.

Ryaboshapka was speaking after being asked about a document from the general prosecutor's office that was leaked at a separate press conference by three lawmakers earlier on Wednesday.

ADVERTISEMENT

The document, only part of which was visible, showed Kulyk suspected Zlochevsky of offences including using his official position to embezzle 800 million hryvnias ($33 million) of money belonging to the central bank.

The investigation is effectively on hold, however, because the Ukrainian authorities cannot determine Zlochevsky's whereabouts.

The central bank did not respond to a request for comment.

Giuliani has previously told Reuters he met Kulyk in Paris. He said at that meeting Kulyk echoed allegations that in 2016 Joe Biden as Vice President had tried to have Ukraine's then-chief prosecutor, Viktor Shokin, fired to stop him investigating Burisma. Biden has accused Giuliani of peddling "false, debunked conspiracy theories" for repeating these allegations.

Kulyk told Reuters in October that he had been investigating Zlochevsky for around two years.

Reuters could not independently verify the extent of Kulyk's involvement, but a source close to the energy company saw a spike in activity by Kulyk in regards to Burisma after Giuliani's interest in the company and the Bidens had been conveyed to Kulyk's then superior, Yuriy Lutsenko.

ADVERTISEMENT

In late January, Kulyk sent Zlochevsky the first of several summons for questioning, documents seen by Reuters showed.

Zlochevsky has not commented on the summons or an announcement by Ryaboshapka in October that his office was reviewing a series of investigations linked to Zlochevsky.