The unofficial boycott of French wine in the US has cost the country an estimated US$112m (£64m), according to an official study.

According to the National Bureau of Economic Research, at its peak, the boycott resulted in a 26% slump on weekly sales with 13% lower sales in the six months following the US invasion of Iraq.

The Bureau’s study, carried out by economists Larry Chevis and Phillip Leslie at Stanford University, found that from March to August 2003, French wine imports to the US were worth US$695m (£400m). This was a drop on the previous year, and 2004 as a whole was down 8% on 2003.

The boycott was a result of France’s opposition to the war in Iraq in 2003. Anti-French feeling at the time was running high and many media outlets, including the New York Times, reported on the rejection of French products – most famously with the cafeteria in the US House of Representatives renaming their French Fries as Freedom Fries.

Gallup Polls showed that in May 2000, 50% of Americans considered France to be an ally. By April 2003, that number had dropped to 18%.

Chevis and Leslie examined weekly sales data from supermarket chains in Boston, Los Angeles, San Diego and Houston – and were surprised by the strength of the results.

‘Economists tend to be sceptical of the economic effects of boycotts,’ they said. ‘But this example shows that business should indeed be concerned.’

Anthony Barton of Bordeaux’s Chateau Léoville Barton was more sceptical of the results.

‘I would like to pinpoint a drop in French wine sales to something as specific as opposition to the Iraq invasion, but unfortunately it is more complicated than that,’ Barton told decanter.com. ‘Statistics are like a bikini – they give you the idea, but hide the details.’

Written by Jane Anson