By Douwe Miedema, European Wealth Management Correspondent

VADUZ (Reuters) - The reputations of Liechtenstein and its banks were under the spotlight on Monday, under pressure from a probe in Germany that may show hundreds of prominent people hid their wealth in the tiny principality to dodge taxes.

Liechtenstein, one of only three remaining countries on the Organization for Economic Cooperation and Development's (OECD) blacklist of uncooperative tax havens, has been trying to burnish its reputation for years, saying its banks offered financial expertise, not ways to evade tax.

But Germany said this weekend it had uncovered hundreds of prominent tax dodgers in the country when it paid an informant 4.2 million euros ($6.17 million) for a compact disk with client data from a Liechtenstein bank.

Among those under investigation was the outgoing chief executive of Deutsche Post (DPWGn.DE: Quote, Profile, Research), the logistics and mail firm.

"This is potentially a disaster for them (Liechtenstein and its banks). They've been struggling to overcome a bad reputation and become a more salubrious off-shore center," said Ted Wilson, a wealth management consultant at Scorpio Partnership.

About a third of Liechtenstein's economy depends on its banks. Together, they hold some 160 billion Swiss francs ($145.1 billion) in client assets, making the entire country's banking system roughly as big as one mid-sized Swiss bank.

A spokeswoman for the Liechtenstein government said the country would make an official statement on Tuesday, and declined to comment before that. The country's banking association could not be reached for comment.

Media in Liechtenstein criticized the way Germany had obtained the data, and bankers said the country had come a long way in improving its reputation for fighting financial crime.