The market regulatory body accused Osborne for engaging in market abuse by inappropriately disclosing clandestine information to Greenlight Capital, about a planned equity sale by Punch.

Greenlight, which had 13.3% of Punch’s shares, disposed 11.65 million shares, reducing its holding to 8.9% over the four days after the call with Osborne and altered a loss of £5.8m when Punch’s shares reduced to 29.9% after it announced plans to raise £375m in June 2009, according to FSA.

The FSA’s acting head of financial crime Tracey McDermott said that Osborne was engaged in serious market abuse though his actions were unintentional. He failed to raise the issue with senior management, legal or compliance personnel or take any steps to address the risk of market abuse.

"His actions undermined the orderliness and integrity of the market and the high penalty reflects the seriousness of his breach," McDermott added.