The 44-year-old Lovše, who was detained by police for questioning on Wednesday, was ordered by the judge to remain in custody pending charges against him because he is a flight risk, the STA was told by the Ljubljana District Court.
Contributing to the decision was the fact that Lovše is a resident of Monaco, while he owns properties elsewhere abroad, several media outlets reported. He can be held for up to 30 days before he must be released or the prosecution must ask for an extension of the custody.
Lovše is one of three suspects in the investigation regarding abuse of office in the case of the fallen empire around Diners Club Slovenije, with another being released on Friday and a third detained by police after returning to Slovenia.
The media have named the second suspect who was released by the judge on Friday as representative of Diners Club Slovenija Saša Pušnik and the man detained late on Thursday as another representative of the company Anton Horvatič.
The decision by the judge came as the 48-hour period of police detention expired.
The three men were detained by police in connection with the investigation into the dealings of Diners Club Slovenije as part of which at least EUR 9m in damage was allegedly caused to the company.
The investigation was launched on Wednesday with more than a dozen house searches conducted at various locations in Slovenia.
The case has sparked extreme media interest in Slovenia as Lovše is regarded as one of the most influential people in financial circles in the country.
He rose to fame in the late 1990s as a 30-year-old businessman when he took over the reigns of struggling shoemaker Peko and has since made his name as a director and owner of Diners Club Slovenija franchises in Slovenia, Italy and Croatia.
Having studied in the US, Lovše is regarded as extremely well connected, having often boasted of his links on Wall Street and in US financial circles.
In 2007 he was ranked by the Manager magazine as the fifth richest Slovenian with total assets of EUR 73m. He also served a two-year stint as head of the Slovenian Ski Association from 2010 to 2012 and as the chair of the American Chamber of Commerce (AmCham) in Slovenia for two years until August 2011.
His fall from grace began in May when central bank Banka Slovenije stripped Diners Club Slovenije of its licence for financial transactions due to unpaid liabilities to retailers.
The decision left 80,000 cardholders in Slovenia unable to use their cards. It forced Diners Club International to intervene to bring about a solution as part of which the franchise has passed to Erste Card Club, a subsidiary of Austria's Erste bank group.
Business daily Finance reports on Friday that the investigation is focusing on the operations of DC Finance, an offshoot of Diners Club Slovenija, from where Lovše is said to have channelled money. It says that the difference between the accounted claims to cardholders and the official figures on the books indicate a EUR 14m gap.
The paper says that Lovše had run up most of the debt to his company through the use of credit cards but was never charged by Diners Club Slovenije for these amounts. The police are also investigating the use of liquidity loans given to the company by the banks Hypo Alpe Adria and Unicredit Slovenija to pay retailers.
Banka Slovenije stripped Diners Card Slovenije of its licence after it had become clear that it had run up extensive debts - reportedly in excess of EUR 20m - to retailers. These will now be repaid with the help of Diners Club International.