By Imogen Foulkes BBC correspondent in Bern

Switzerland's relations with the European Union are being put to the test in a battle over who has the right to use the name champagne.

Switzerland, which is not a member of the EU, has agreed a series of bilateral accords with Brussels, which come into force at the start of June.

Under the terms of one of the accords the Swiss village of Champagne will no longer be able to give its name to the wine it produces.

The Swiss Government agreed to the clause at the insistence of France.

But now Swiss wine-growers are mounting a last-ditch legal battle to have the agreement overturned.

Defending rights

The tiny Swiss village of Champagne, with a population of only 660, has been making wine for at least 800 years.

France makes more than 300 million bottles of champagne a year

The village's name was first recorded in the 13th century and since that time wine produced there has been called champagne.

The Swiss village only produces 280,000 bottles of its champagne a year, compared to 300 million of the French variety.

French wine-growers have already successfully pressured the fashion designer Yves Saint Laurent into dropping plans to call a perfume Champagne, so it seemed unlikely that a handful of Swiss farmers would be able to defend their right to the name.

But this has not put off the citizens of the Swiss village of Champagne from beginning legal proceedings at the European Court of Justice in Luxembourg.

Challenge

The case could threaten Switzerland's bilateral accords with the EU.

The seven agreements - covering important issues such as the free movement of people, transport and trade - took years to negotiate and Brussels always insisted that all seven would have to be agreed or none at all.

Now, just as the agreements are about to come into force, one small clause - which if removed could negate all the agreements - is being challenged.

And the producers of Swiss champagne are determined.

Just because France is much stronger, they say, it does not mean it should be allowed to silence those who are weaker.