Operations at Ukio Bankas - which is also controlled by the Jambos owner - have been suspended amid fears it has taken too many risks.
However, Tynecastle director Sergejus Fedotovas insists the bank's current predicament will have "very little" effect on Hearts.
Kanus-based Ukio Bankas - which Romanov owns 64.9 per cent of - provides the club with banking and debt services but is separate from another of Romanov's firms Ukio Banko Investicine Grupe (UBIG), the company which controls the Gorgie side.
Fedotovas told the club's official website: "The Board wishes to make it clear that Heart of Midlothian plc and Ukio Bankas are two separate companies.
"Hearts is majority-owned by UBIG, a multi-national business conglomerate. UBIG is an entirely separate entity and stands alone from Ukio Bankas.
"At a service and operational level, Ukio Bankas does provide the club with some banking services and debt facility and the Board is liaising with Ukio Bankas on these matters.
"The supporters of Hearts can be assured that the Board of the club continues to be diligent in financial matters and we believe that today's events in Lithuania will have very little affect on our day-to-day business."
Today's development is the latest in a long-running financial saga at Tynecastle.
The club's 2012 accounts show that it owes UBIG £24million while it has faced two separate bills from Her Majesty's Revenue and Customs in recent months.
Hearts had to appeal to their supporters for help late last year when the taxman issued them with a winding-up order over an unpaid £1.75million sum.
A share issue brought in £1.79m as fans rallied to the cause, while the club struck a deal with the Revenue that will see £1.5m repaid over three years.
The club also paid a separate £450,000 bill to the tax authorities just before Christmas, but financial concerns remain with an expected £2million shortfall in turnover that has already affected payment of wages and bonuses to players, leading the Scottish Premier League to issue Hearts with a series of transfer restrictions.
Shares in Ukio Bankas fell as much as 16 percent today in Vilnius, the biggest drop in a single day since February 2000, closing down 12 percent at 0.095 euro.
The company's value of 32.9 million euros (£28.2 million) is less than half what it was a year ago.