A leaked European Commission audit has concluded that billionaire Czech Prime Minister Andrej Babis has a conflict of interest as he still controls one of his country's largest companies, a Czech newspaper reported Tuesday.

The document also suggests that Babis's company should return some 451 million Czech crowns (17.6 million euros, $19.5 million) in EU and state subsidies that were paid out illegally. The commission ordered the audit last year at the request of an anti-corruption watchdog and a Czech opposition party that questioned Babis's dual role and whether his sprawling Agrofert holding was entitled to receive hefty EU agricultural subsidies if he controlled it.

Babis, the fourth wealthiest Czech according to Forbes magazine, has denied any wrongdoing, saying he had transferred the Agrofert food, chemicals and media holding into two trust funds, as required by a new Czech conflict of interest law. The leaked audit concluded otherwise.

"Andrej Babis is still the owner of the Agrofert holding and, since February 2017, of two trust funds which he directly controls," reads a Czech translation of the audit published by Denik N broadsheet on its website.

Babis "has a direct economic interest in the holding's success," the daily added. According to the leaked audit all EU and state subsidies paid to Agrofert since February 9, 2017 when the conflict of interest law took effect, were illegal.