"African farmers must receive a fair reward for their work," Chirac said in Bamako, Mali, days before a key ministerial meeting in Hong Kong on global free trade negotiations.
Agriculture has proved the thorniest issue in the four years of talks at the World Trade Organisation amid calls by developing countries for rich nations to slash subsidies and import tariffs which are accused of skewing farm trade against the poor.
France, which received 9.418 billion euros ($11.298 billion) in 2004, is the top recipient of EU agricultural subsidies.
"Cotton, produced by 33 African countries, is symbolic of inequitable trade which deprives our countries of indispensable resources ..." Malian President Amadou Toumani Toure told the opening of the Bamako summit on Saturday.
"Are we going to continue in Africa sowing cotton to harvest deficits, while others, more affluent, sow the same cotton to harvest subsidies?"
Benin, Burkina Faso, Chad and Mali, for which cotton is a vital export, have said their interests must not be sidelined at the Hong Kong summit from 13-18 December.
The European Commission has said it will push for a substantial cut in cotton subsidies at the meeting.
And Chirac, keen to stress there that France was the "tireless advocate of Africa", called "upon the United States to remove the subsidies to their cotton producers as Europe has undertaken to do."
On Saturday the French president said: "Such subsidies impoverish millions of small African producers, despite the competitiveness of the latter."
Cotton-producing African nations
want their interests protected
The Association of African Cotton Producers (AProCA) expressed satisfaction at France's statement.
"It's the first time he has spoken so clearly on the issue ... pending things becoming concrete as we hope," said the association's permanent secretary Mamadou Ouattara.
Washington's payouts to the US cotton industry have been ruled illegal by the Geneva-based WTO. The US is the world's biggest cotton-producing nation.
The 2700 largest US cotton producers split up one-third of all subsidies paid worldwide in the sector, according to a study sponsored by West African cotton producers released last month.
US trade chief Rob Portman, in advance of a trip to Burkina Faso last month, outlined US proposals at the WTO to cut export subsidies for its agricultural goods by 2010, and to scrap an export-subsidy programme specifically for US cotton.