"I find that the idea in particular of introducing, if I have correctly understood, a one-off tax in the City of London, is a very charming idea that could provide a lesson or two," she told reporters with a smile on the sidelines of a meeting of the centre-right European People's Party.
She added that it should not be taxpayers who shoulder the burden of the financial crisis but "banks and their employees."
In a joint opinion piece in Thursday's Wall Street Journal, British Prime Minister Gordon Brown and French President Nicolas Sarkozy urged other leaders to impose a tax on bonuses.
"We agree that a one-off tax in relation to bonuses should be considered a priority due to the fact that bonuses for 2009 have arisen partly because of government support for the banking system," wrote the leaders.
Britain announced Wednesday it was slapping a one-off 50-percent tax rate on bonuses above £25,000 ($40,700) to recoup cash spent saving the financial sector during the crisis.
According to reports in the French press, Paris is also poised to impose a 50-percent tax on bonuses above €27,000 ($39,800), although officials stressed that the exact format has not yet been decided.