A prominent Swiss billionaire has called for higher taxation of the rich as his country overwhelmingly rejected a proposal to introduce a 50% tax on inherited fortunes of 50 million Swiss francs ($62 million) and above.

Alfred Gantner, a co-founder of private equity firm Partners Group said increasing concentration of wealth was a global problem in remarks published on Monday in Swiss newspaper Tages-Anzeiger, which interviewed the entrepreneur last week.

"It can't be that a few people in this country have huge fortunes and others don't know how they're going to pay their health insurance and their rent," Gantner, who also refers to himself as Fredy, was quoted as saying.

If nothing is done to address the problem, then the "Elon Musks, Mark Zuckerbergs and Fredy Gantners will amass a whole lot more money in the next 20 years," Gantner said.

Switzerland is one of the world's top wealth management hubs and around 2,500 taxpayers in the country have assets worth more than 50 million francs, according to Swiss tax authorities.

Over 78% of Swiss voters in a referendum on Sunday rejected the proposed inheritance tax, more than polls had forecast.

Gantner, who described luck as an important part of accumulating a large fortune, said inheritance taxes were not the way forward, arguing they can easily be circumvented.

"We need progressive wealth taxation," he said. "For example, one could say that above 200 million Swiss francs, taxes of 1% are due. At half a billion, it would be 1.2%, at one billion, 1.5%, and so on."

Gantner, who is pushing for Switzerland to reject an agreement that will deepen its economic ties with the European Union, appears at number 1045 in the 2025 Forbes Billionaires list with an estimated net worth of $3.5 billion.