A popular and flamboyant figure in France, the 63-year-old Depardieu is the latest wealthy Frenchman to seek shelter outside his native country after tax increases by Socialist President Francois Hollande.
Prime Minister Jean-Marc Ayrault described Depardieu's behaviour as "pathetic" and unpatriotic at a time when the French are being asked to pay higher taxes to reduce a bloated national debt.
"Pathetic, you said pathetic? How pathetic is that?" Depardieu said in a letter distributed to the media.
"I am leaving because you believe that success, creation, talent, anything different must be sanctioned," he said.
An angry member of parliament has proposed that France adopt a U.S.-inspired law that would force Depardieu or anyone trying to escape full tax dues to forego their nationality.
The "Cyrano de Bergerac" star recently bought a house in Nechin, a Belgian village a short walk from the border with France, where 27 percent of residents are French nationals, and put up his sumptuous Parisian home up for sale.
Depardieu, who has also inquired about procedures for acquiring Belgian residency, said he was handing in his passport and social security card.
Culture Minister Aurelie Filippetti said she was outraged by Depardieu's letter, adding that he had for years been supported financially by public money for the film industry.
"When we abandon the ship and desert in the middle of an economic war, you don't then come back and give morality lessons," she told BFM-TV. "One can only regret that Gerard Depardieu doesn't make a comeback in silent movies."
He said he had paid 145 million euros (AUD$180.6 million) in taxes since beginning work as a printer at the age of 14.
"People more illustrious than me have gone into (tax) exile. Of all those that have left none have been insulted as I have."
The actor's move comes three months after Bernard Arnault, chief executive of luxury giant LVMH and France's richest man, caused an uproar by seeking to establish residency in Belgium - a move he said was not for tax reasons.
Belgian residents do not pay wealth tax, which in France is now levied on those with assets over 1.3 million euros (AUD$1.62 million). Nor do they pay capital gains tax on share sales.
"We no longer have the same homeland," Depardieu said. "I sadly no longer have a reason to stay here. I'll continue to love the French and this public that I have shared so much emotion with."
Hollande is pressing ahead too with plans to impose a 75-percent supertax on income over 1 million euros (AUD$1.25 million).
"Who are you to judge me, I ask you Mr Ayrault, prime minister of Mr Hollande? Despite my excesses, my appetite and my love of life, I remain a free man."
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