The principle of euro-zone bailouts on Wednesday gained legal support in a German court while uncertainty about the Continent's finances and future actions persisted amid economic and political turmoil in Italy and Spain.

"Uncertainty seems to be the word of the day," said Raoul Ruparel, a London-based economic analyst with the Open Europe think tank who advises against investing in Europe for now. "It's really a time to batten down the hatches in terms of exposure to Europe."

Earlier in the day, the Federal Constitutional Court in Karlsruhe threw out a complaint questioning the legality of Germany's share of last year's €110 billion ($154.6 billion) loan package for Greece from the European Union and the International Monetary Fund, as well as a separate €750 billion rescue fund approved last year to stop the spread of the Greek debt crisis.

The plaintiffs included a law professor, three economists, former Thyssen AG chairman Dieter Spethmann and a lawmaker from the Bavarian sister party of Chancellor Angela Merkel's Christian Democratic Union. They had argued that the aid packages were illegal because they were not submitted to the German parliament for approval.

The court rejected the arguments but cautioned that its decision should not be interpreted as a "blanket" approval for future rescue packages. It underscored that the government should seek approval from the parliament's budget committee for guarantees it covers under the European Financial Stability Facility, or EFSF, scheme.

"Parliamentary decisions about taxing and spending are a central element of democratic self-government under the constitution," Andreas Vosskuhle, president of the court, said in the decision. "As representatives of the people, the elected members of parliament thus also need to remain in control over elementary budget decisions."

While the decision was in line with expectations, analysts said it adds uncertainty to the euro-zone crisis.

"The ruling gave more say to the Bundestag's budget committee, which institutes another layer of negotiations the German government needs to follow," Ruparel said. The decision also suggests that any future move toward eurobonds could be deemed unconstitutional, even with agreement from the Bundestag, Ruparel said. "The full implications remain unclear," he added.

Merkel will have a tough fight to win the backing of her own center-right coalition to raise Germany's share of EFSF loan guarantees from €123 billion to €211 billion. On Sept. 29 the German parliament will vote on the proposal. If ratification is secured only with the support of opposition parties, it would weaken Merkel's already shaky leadership.

Some observers believe that nothing less than eurobonds can salvage the union, and certainly financial markets remain roiled. In Spain, bond yields hover at their lowest level in two years compared to Italian rates ahead of a Senate vote on Prime Minister Luis Rodriguez Zapatero's constitutional amendment to ban budget deficits. Thousands of people took to the streets of Madrid Tuesday night to protest the measure.

In Italy, Prime Minister Silvio Berlusconi's political future looked shaky amid squabbling over austerity measures required by the European Central Bank in exchange for support.

The package goes to the Italian Senate Wednesday evening for a confidence vote after ECB President Jean-Claude Trichet demanded quick, decisive action to save Italy's credit reputation. The Frankfurt-based ECB has been buying up Italian bonds in the past month in a move to reduce the country's borrowing costs and keep it from becoming the next euro-zone country to require an international bailout.

If Wednesday's vote fails, Berlusconi could be forced to resign.

Last week, the EU approved the next tranches of aid payments to Portugal and Ireland, saying that both countries were on track to get their public finances back in order and restore competitiveness to their financial sectors.

Next week, a team from the European Commission, IMF and ECB is due to return to Greece to determine whether the embattled country is meeting conditions for the next tranche of emergency loans, due in September.