Breweries in Canada are struggling to source enough cans to package their products after the trade war with America began to take effect.

The aluminum tariff brought in by the US and then Canada as a retaliatory measure earlier this year prompted large soft drink makers in Canada to stock up on metal.

This has led to a shortage and a knock-on effect for the smaller, craft beer manufacturers, who are in some cases now getting into financial difficulties.

Beer Canada's Luke Harford told the Associated Free Press that with small businesses canning 50 per cent of their product, the industry is facing additional costs of $10.3 million this year because of tariffs.

"It's a terrible time for brewers," he commented, adding that although can manufacturers in Canada are now racing to increase production, craft brewers "working hand to mouth will suffer in the interim".

Canada is the world's third largest producer of aluminum, but according to the government statistical agency, it still imports more than two billion cans each year, many of which come from the US.

There are currently 817 brewing facilities in Canada and although it has been suggested that they simply switch to bottles, many manufacturers have either a canning or a bottling line and so could face bills of hundreds of thousands of dollars were they to implement new equipment.

The government is currently being lobbied by the industry to exempt beer cans from the new tariffs, but no results have yet been forthcoming.