Champagne houses in France on Monday issued a plea for diplomatic help over a new Russian law reserving the term “champagne” for Russian-produced sparkling wines, which interrupted supplies from the local market leader Moet Hennessy.

French producers are fiercely jealous of the AOC, or Controlled Appellation of Origin, that is supposed to give them exclusive use of the word in countries that adhere to the Lisbon Agreement on distinctive geographical indications.

But Russia is not a signatory, and on Friday President Vladimir Putin signed a law that will forbid the use of the Russian translation of champagne – “Shampanskoe” – on imported bottles.

French producers can still use the word in French, but will also have to write “sparkling wine” in Cyrillic on the back of bottles – a heresy for brands that say nothing on Earth can match their distinctive bubbly.

“The Champenois call on French and European diplomats to obtain a change of this unacceptable law,” the Champagne Committee, which groups grape growers as well as producers in France’s northeastern Champagne region, said in a statement.

It denounced a “scandalous” move that “calls into question more than 20 years of bilateral talks between the EU and Russia on the protection of AOCs.”

Moet Hennessy, owned by the luxury conglomerate LVMH, said on Sunday that it would comply with the law and would resume exports of its brands, including Dom Perignon, Moet & Chandon and Veuve Clicquot, “as soon as possible”.