By Tom Sims and Hans Seidenstuecker

Wirecard's administrator said on Tuesday that more than 100 investors have expressed interest in buying the collapsed German payments firm's core business and holdings.

The firm filed for insolvency last month owing creditors 4 billion euros (3.5 billion pounds) after disclosing a 1.9 billion euro hole in its accounts that its auditor EY said was the result of a sophisticated global fraud.

"The aim is to find timely investor solutions in the interest of creditors, employees and customers," administrator Michael Jaffe said in a statement after a creditors meeting.

The potential sale of Wirecard North America's assets was most advanced, Jaffe added, with investment bank Moelis & Company already mandated to conduct a sale.

Sale processes are also being initiated for other international holdings as well as Wirecard's core business, he said, adding that most of its customers were being constructive and showing an interest in a speedy sale process.

Jaffe said potential investors would soon be able to start due diligence procedures in virtual data rooms.

Reuters reported on Monday that Jaffe was likely to raise only about 400-500 million euros for Wirecard's assets, citing one person close to the matter. This would be about 10% of the total creditors are owed.

Deutsche Bank's chief executive said on Tuesday it was too early to say how it might help Wirecard Bank, adding that its own exposure to the Wirecard fraud was very limited.

Germany's largest bank said last week that it was working with financial watchdog BaFin and Wirecard's administrator on possible support for Wirecard Bank.

While it was "too early to judge" how Deutsche Bank may be involved, CEO Christian Sewing said it was "almost an obligation" to look at Wirecard Bank for opportunities or to stabilise it given his company's focus on transaction banking.

"We all now need transparency and that's the first task," Sewing told a webcast event organised by Bloomberg News.

Deutsche Bank said last week that it was ready in principle to support Wirecard Bank "in the context of a continuation of business operations" if assistance became necessary.

Separately, European Union finance ministers are due to discuss stronger regulation of payment providers at a meeting this week, a German government official said.

"Europe-wide rules are urgently required," the official added. Germany's regulation of Wirecard has come under intense scrutiny since the rapid demise of the former fintech star.

($1 = 0.8868 euros)

(Reporting by Tom Sims and Hans Seidenstuecker; Additional reporting by Christian Kraemer and Emma Thomasson in Berlin; Editing by Maria Sheahan, Michelle Martin and Alexander Smith)