Bollinger has denied that its new bottle shape copies Champagne producer Bruno Paillard, saying that the redesign is based on 19th-century bottles from its cellars.

Paillard accused Bollinger of directly copying his bottle design, and said that if experts establish the case, he will start legal action.

“I am deeply shocked that a House ... allows itself to copy an existing bottle. At this stage we have only superimposed images of their bottle on ours and recorded that they are rigorously identical,” claimed Paillard.

He threatened legal action saying, “if it turns out they are exactly the same model, we will have to start a judicial process - our bottle being registered in many countries.”

Paillard said he designed his bottle 30 years ago to stand out from others, but also to “increase the exchange surface between the wine and the lees” and “enhance complexity”.

A spokesman for Bollinger said: “We do not wish to comment directly on claims made last week regarding the redesigned shape of our bottle. However, as explained at the initial launch in May, we would like to underline the fact that this redesign drew inspiration from the collection of bottles in our cellars which date back to the mid-19th century.”

Bruno Paillard established the Champagne House which bears his name in 1981. Champagne Bollinger dates back to 1829.