A transatlantic battle to stop Canada's only single malt whisky distiller from using the word glen has been lost after almost 20 years.

The trade group representing some of Scotland's biggest drinks firms had been claiming the use of the word implied Scottishness.

The Scotch Whisky Association opposed the use of the name Glen Breton Rare, arguing that consumers would be confused with other popular home grown brands which make use of the word glen, such as Glenfiddich, Glenlivet and Glenmorangie.

However, the Canadian Trademark Opposition Board has rejected the association's claim of unfair competition, saying the use of the word glen cannot be seen as exclusively Scottish.

Despite the ruling, the legal dispute, which is thought to have cost both sides thousands of pounds, is set to continue.

The SWA plans to appeal on the grounds that the principle of barring the use of glen on whisky labels has already been established in the laws of various countries.

It says it has successfully won legal battles over the use of Glen Shire in Australia, Glen whisky in New Zealand, Glen Forbes in India and Glen Castle in the US.

However, David Martin, member of the opposition board, said in the ruling: "If the opponent truly believed that the world glen' merits special protection for producers of Scotch whisky, it should have long ago taken steps to protect that word as a geographical indication of Scottish origin much as it did for the words scotch whisky'.

"Alternatively it was open to the opponent to register glen' as a certification mark and thereby enforce particular standards for whisky sold under that mark by its members and others.

"Since it chose to do neither, it cannot preclude others from registering glen-prefixed marks for legitimate use in commerce with non-Scotch whiskies."

The board also concluded there was no evidence put forward by the Scotch Whisky association to suggest Canadian consumers primarily associated the word glen with whisky produced in Scotland.

The Glenora distillery, based in Inverness County, Nova Scotia, launched Glen Breton Rare in 2000.

In defending the right to use the word glen, Glenora said the brand name derived from the community and region in which Glenville and Cape Breton and the town of Glenora Falls were to be found.

It argued Cape Breton had very strong Scottish roots because Scots settled there more than 200 years ago.

It pointed out that the water source for the whisky is MacLellan's Brook, known as a glen stream and said that glen is commonly used in place names all over Nova Scotia.

The distillery said it was not trying to pass itself off as Scottish pointing to the label emblem, a maple leaf, a symbol widely associated with Canada as it features prominently on the national flag.