In control of a crucial portfolio at a time of heightened budgetary discipline and rising taxes in France, as well as the European debt crisis and stagnant growth, Mr. Cahuzac was a highly visible public figure.

But reports that he had once held an undeclared Swiss bank account were widely considered damaging to President François Hollande, whose approval ratings are low and who won election last year in part on a pledge to be ethically blameless.

Mr. Cahuzac has angrily denied ever holding such an account, an accusation first made in December by Mediapart, an investigative Web site. Based largely on an audio recording said to be of Mr. Cahuzac in 2000, those reports suggested that he held an account with the Swiss bank UBS until 2010.

Mr. Cahuzac will be replaced as budget minister by Bernard Cazeneuve, the minister of European Affairs, Mr. Hollande said.

Mr. Cahuzac, who was trained as a plastic surgeon, announced that he would sue Mediapart for defamation, but a preliminary judicial inquiry was opened into the case in January. The Paris prosecutor’s office said Tuesday that the inquiry had established with moderate certainty — based on witness testimony and voice analysis — that the recording was indeed of Mr. Cahuzac, and that a formal investigation would be opened.

In the recording, posted online by Mediapart, a man identified as Mr. Cahuzac can be heard to say, “It bothers me to have an account open over there — UBS, after all, is not necessarily the most hidden of banks.”

He resigned “out of respect for the good functioning as much of the government as of the justice system,” Mr. Cahuzac said in a statement.

“This changes nothing as regards either my innocence or the calumnious character of the accusations launched against me,” he continued, “and I will now devote all my energy to proving this.”

Those accusations, along with the months of denial punctuated by an abrupt departure from the government, largely mirrored a financial scandal under Mr. Hollande’s predecessor, Nicolas Sarkozy, involving the labor minister, donations to Mr. Sarkozy’s political party and the sale of a state-owned property.

Mr. Sarkozy was dogged by persistent accusations of corruption, some of which brought judicial investigations involving him or close associates. Such has not been the case for Mr. Hollande, who has cast himself as a “normal” president.

Mr. Hollande thanked Mr. Cahuzac in a statement Tuesday evening, and saluted his decision to resign “to better defend his honor.”

Article source: http://www.nytimes.com/2013/03/20/world/europe/french-minister-steps-down-in-swiss-bank-investigation.html?partner=rss&emc=rss