RBS fears that Europe is on the cusp of "system-wide convulsion" after yields on Spanish 10-year bonds reached post-EMU records of 6.34pc this week, and Italian yields topped 6pc. "We believe that Spain has entered the danger zone for yield levels," said Harvender Sian, the bank's credit strategist, who fears the "point-of-no-return" may be 6.5pc. "Given that Spain [and likely soon Italy] has entered this territory, there is a growing risk that a large systemic risk event is plausible in the near term and if not then in a matter of weeks."