The rate of return demanded by investors for Italian 10-year bonds briefly soared above six percent Monday on the secondary market as concerns mounted about eurozone debt despite a Spanish bank rescue.
Shortly before 1700 GMT the yield on benchmark Italian 10-year bonds rose to 6.004 percent from 5.758 percent at Friday's close, breaking the six percent barrier considered to be a level unsustainable in the medium term, for the first time since early June.
The yields later slipped back under six percent.
Italian bond yields, like Spanish yields, initially fell on response to eurozone finance ministers throwing Spain a lifeline of up to 100 billion euros ($125 billion) to rescue its battered banks.
However Spanish bond yields later rose on concerns that the rescue funds will add to the country's debt.
Italian stocks closed the day down 2.79 percent.