Spain had to pay higher rates Tuesday to raise 3.05 billion euros ($3.72 billion) in short-term funds, coming under pressure again on the markets on concerns that Madrid will need a full debt bailout.
The treasury said it sold 3-month bills at 2.434 percent, up from 2.362 percent at the last similar auction in late June, with 6-month bills rising sharply, to 3.691 percent from 3.237 percent.
It said bids came to 9.0 billion euros, reflecting strong demand for the debt, which carries very high rates for such short maturities.
Spain's long-term borrowing costs have soared in recent days to well above the danger line of 7.0 percent, hitting levels that forced Greece, Ireland and Portugal to seek EU-IMF bailouts.
The yield or rate of return on the benchmark 10-year Spanish government bond was higher again Tuesday, at 7.563 percent, while the Madrid bourse slumped more than 2.0 percent in late morning trade.
Analysts said that with the central government's finances so strained, news that some of the country's 17 regions were looking for help from Madrid was enough to tip the tables against Spain on the markets.
A report Tuesday said Spain wanted a partial bailout from its European partners to meet its immediate financing needs and so avoid an imminent collapse.
The Economista daily said the government wanted a line of credit to cover 28 billion euros ($34 billion) in debt maturing in October since raising the money on the financial markets was now too expensive.
Analysts say that to avoid disaster, Spain needs the European Central Bank to step in quickly and buy up Spanish government bonds so as to bring down its borrowing costs.