The yield on Spanish debt has shot up to 5.7% over fears of contagion from the Greek debt crisis.

The yield has been rising steadily since the middle of last week as investors fret over whether the Greek Parliament will approve more austerity measures as a condition for obtaining more bailout money.

Despite the rise in borrowing costs, Spain''s finance Minister Elena Salgado said Monday that Spain had no trouble financing itself in the markets and blamed the current spike to tensions related to the Greek debt crisis.

Deutsche Bank Chief Executive Josef Ackermann said on Monday that contagion of Greece''s debt problems to the rest of Europe could be worse than the 2008 collapse of the Lehman Brothers investment bank.

Greece needs 12 billion euros ($17 billion) in European and IMF aid to avoid a default on its debt mountain in mid-July that could spread contagion across the euro currency area and send shock waves around the world economy.

"If it is Greece alone, that''s already big. But if other countries are drawn in through contagion, it could be bigger than Lehmans," he said at a Reuters banking conference on Monday.

His words echoed statements top European Central Bank policymaker Juergen Stark made earlier, when he said the impact of a Greek debt restructuring on Europe''s markets could eclipse the insolvency of Lehman Brothers, which marked the start of the global financial crisis.

French banks have agreed to roll over holdings of Greek debt for 30 years, but no comparable deal has been reached in Germany so far.

The results of a euro poll, meanwhile, revealed nearly three quarters of Germans (almost 4 in 5) have little confidence in the euro.

Two thirds of Germans also said they had doubts the euro zone rescue mechanisms could stabilise the currency zone.

Some opinion polls suggest there is a difference between shaky confidence in the euro and in ongoing bailout discussions. According to another survey, 56% of Germans wanted to keep the Euro.