No other details have been revealed beyond the firm being owned by J&T Private Equity Group, which public records suggest is in turn owned by the Czech J&T Finance Group.

The revelation comes amidst intense speculations about the reshuffling of Petrol stock, which has been going on for months.

About 12% of Petrol was sold in autumn last year by two banks and the holding Istrabenz. The buyers were not revealed as the stock was transferred to a fiduciary account in the Czech Republic.

This triggered a flurry of takeover speculations and led late last year to restoration of a provision requiring an individual investor to get the government's approval for the acquisition of a controlling stake in Petrol.

The state-owned SOD fund remains the biggest single shareholder (19.7%), with another para-state fund, KAD, holding 8.3%.

Public records still show the Czech fiduciary account as the second biggest shareholder at 12.8%.