Europe was plunged into fresh market turmoil as this week's visit by Greece's creditors rekindled concern the currency union will splinter and the first call for bailout aid by a Spanish region caused borrowing costs to surge.

Stocks and the euro fell before the arrival in Athens tomorrow of Greece's troika of international creditors — the European Commission, the European Central Bank and the International Monetary Fund. In Spain, Catalonia joined a list of the country's regions that may tap aid from the central government in Madrid, spurring Spanish 10-year yields to surge above 7.5 percent for the first time.

"The problem in the region is profound, but the pace that it has been dealt with was slow," said John Stopford, head of fixed income at Investec Asset Management, which oversees $98 billion. "The bank bailout for Spain is far from sufficient to deal with the country's problems."