Michel Barnier told le Figaro in an interview published on Tuesday that he could not rule out that some European banks would need state aid.

"The days are behind us when the banks can be bailed out with taxpayer funds," he said. "But it cannot be ruled out that some banks will need state help. The European Commission is prepared for such a scenario and will oversee it."

Investors have sold off European banking shares in recent months, spooked by concerns over whether financial institutions could withstand a default of Greece as well as another economic downturn.

The IMF recently urged Europe to move towards recapitalising its banks, but officials in Europe have resisted such across-the-board calls.

Asked whether it was time to recapitalise Europe's banks, Barnier replied: "The IMF was correct to emphasize the risks of a second global recession. But I do not share its view on the capital needs of the banking sector."

Barnier pointed out that nine banks had failed stress tests carried out in July, and 16 "barely made it" and needed to be recapitalised. "We would prefer this to be done first through private means," he said.