Jerome Cahuzac, who last month bowed to pressure and also resigned from parliament, told the regional daily Depeche du Midi he made the decision because he feared a violent hate campaign against him and incessant media harassment would make it impossible to get his message across to voters.
Any money left over from the sums he tried to hide abroad — after paying what he owes the state — will go to local charities, he added.
That money has already been transferred back from abroad to France and was at the disposition of the authorities.
"I will pay my debt. And I will give what remains, if there is any, to charitable works," Cahuzac added.
For months, Cahuzac — who as budget minister was responsible for cracking down on tax fraud — had denied reports by the Mediapart news website that he had stashed money abroad to avoid paying taxes.
He only admitted the wrongdoing when prosecutors opened a formal investigation after experts said the voice on an incriminating tape produced by Mediapart was probably that of the minister.
In a primetime television interview last month, he said the sums involved in the scandal amounted to some €600,000 euros ($770,000).
The scandal shook French President Francois Hollande's already beleaguered Socialist government, denting the image he had wanted to promote of an administration free of corruption.
Cahuzac now faces being charged for tax fraud.
The by-election for his seat, in the southwestern department of Lot-et-Garonne, will take place in June.