Under France's wine classification system, wines from some 470 regions are each recognised as an 'appellation d'origine controlee' (AOC) -- a system based on the notion of 'terroir' according to which wine-growing areas have specific characters nurtured since Gallo-Roman times.
But according to France's UFC-Que Choisir consumer rights group, slack controls which saw 99 percent of all candidate wines awarded their AOC label in 2005, and pressure to produce higher yields, have led to a collapse in quality.
'For a number of years, we've seen a steady fall in quality in a number of AOCs, which has completely undermined consumer confidence,' Alain Bazot, the association's head, told reporters.
UFC said that one in three AOC bottles were now either of sub-standard quality or insufficiently linked to the region, questioning the impartiality of the AOC award panels made up of local wine professionals.
The association called for the national appellation institute INAO to take urgent steps to correct the situation, if necessary by striking wines from AOC lists, warning it may be 'the last chance' for the system to reform.
AOC wines account for 44 percent of all French wine production, a share that has doubled since the 1970s.