PARIS, Sept. 22 -- An economist behind a wealth tax plan embraced by the French left yesterday urged France's richest person, Bernard Arnault, to show "respect for the truth" after the luxury goods tycoon described him as a "pseudo-academic" who wanted to "destroy the French economy".

With France under pressure to erode its growing debt pile and budget deficit, French economist Gabriel Zucman, 38, has suggested the ultra-rich pay at least a two-per cent tax on their fortune.

The idea has been enthusiastically taken up by the French left, including the Socialist Party, whose support new Prime Minister Sebastien Lecornu could need to ensure the survival of his government.

But it has been denounced by the right, who fear that such a schem...