The minister made the comments after he came under fire himself in the wake of a report on Monday alleging that he too made substantial earnings through freelance contracts aside from his job as the dean and tenured professor at the Faculty of Economics.

Mramor would not comment on the allegation by the Požareport gossip news website that he had himself earned almost as much as the minister who resigned after an upgrade of an online application that traces the flow of public funds showed she made EUR 636,000 on the side over 12 years at her faculty.

"I cannot say anything about my figures, because I've asked to have them calculated. If they are unable to, I'll have to calculate them tonight," Mramor said in Brussels, where he is attending a meeting of EU finance ministers. But he was not sure whether he still had all the documents and figures needed.

He said that as the dean of the Ljubljana Faculty of Economics he had strived hard to have as many projects and programmes possible aside from the regular, publicly-funded ones, which he said assured the faculty quality, international links and excellent results.

He said the efforts contributed to the faculty's links to business and to the quality that was required for accrediting the school in Europe and the US, for which public funds were insufficient.

One of the goals was to ensure the best possible staff, well-paid so they do not go abroad. "Quality faculty teachers can get abroad at least double what they earn here. Many of the best young staff are leaving. They must be given an opportunity to be able to earn something at home."

Mramor had served two years as finance minister (2002-2004) and six years as the dean since 2003, saying that during those eight years he could not work on projects and lectured little in some international courses at home and abroad, for which he was paid fees.

The minister does not find the system that enables faculty staff to earn money outside their regular working hours contentious, arguing that throughout the world experts were encouraged to teach and do research also outside the faculty.

"The system is nothing out of the ordinary, they also have it elsewhere... Colleagues in the US have Friday for themselves and they can busy themselves with market activity the whole day, while we worked in the afternoon, at Saturdays, and Sundays."

This is why he believes Setnikar Cankar's resignation to be a wrong signal, something that he said he had told PM Miro Cerar.

"We need to realise we are now in a market economy. In market economy we try to develop the highest possible quality and offer it to the market. We aren't in communism any more," Mramor said.

However, coalition officials in Ljubljana indicated that they would expect the same development in the case of Mramor as in the case of the resigned education minister should it transpire that the cases were in fact similar.

Cerar told reporters that he was not acquainted yet with details concerning Mramor's fees as he had not had time yet to talk with the minister. But he added that he would get acquainted with the "circumstances".

Meanwhile, MP Marko Ferluga from Cerar's SMC party said that he trusted Mramor, but added that if his earnings turned out to be a situation similar to Setnikar Cankar, the PM would probably have to act the same way as in her case.

Similarly, the head of the deputy faction of the junior coalition Social Democrats (SD), expects Cerar to apply the same standards for everyone. He said he did not know what Mramor was accused of, but he believed him and Setnikar Cankar to be in a similar situation.

Han expects more revelations to follow, which is why he believes it will be "increasingly hard to get competent staff" to serve as ministers.

The view that same standards should apply to everyone was echoed by Uroš Prikl from the coalition Pensioners' Party (DeSUS), who like Han expects Mramor to disclose his earnings and provide sound arguments.

Prikl also called for tackling "anomalies" in the system that enabled some public employees to earn high sums aside from their regular pay.

The SMC deputy group discussed today the recent release of data showing that private individuals made more than EUR 1bn with freelance contracts signed by state institutions in the past 12 years.

They found that no legal wrongdoing had been established in the publicly exposed cases so far, but they called for a reflection on finding an optimal solution to ensure greater transparency in the system.