In a letter to the Canadian newspaper, a spokesman for A.G. Barr said the Canada-specific drink, which doesn't contain banned colouring Ponceau 4R, comes in a specially labelled bottle that the company has been exporting to the country for more than 15 years.
That was of little consolation to Newcastle native Nigel Westwick, who was unable to buy the Scottish favourite from a British food shop in Saskatoon, central Canada, after owner Tony Badger found a selection of the products he buys from the UK unexpectedly seized by customs.
"I couldn't understand the insanity of stopping it coming into Canada, to be honest," Westwick said. "For a country that allows one to buy firearms, guns, bullets, stopping a soft drink suitable for all ages seems a little ludicrous."
Canada has reportedly banned the importing of British foods including Marmite and Irn Bru because of the additives they contain.
Tony Badger, who owns a British foods shop in Saskatoon in central Canada, said he had lost $20,000 (Canadian) - over £10,000 - when his shipments from the UK were seized.
“My understanding was we were importing legally," he told the local CKOM news outlet. "We’ve been declaring it through a customs broker and we’ve never had an issue until now.”
Irn Bru contains the Ponceau 4R food colouring, while Marmite, Lucozade, Penguin Bars and Bovril are all "enriched with vitamins and minerals" unacceptable to the Canadian Food Inspection Agency, according to a letter from the body to Mr Badger.
Unilever has donated £18,000 to the RSPCA following hundreds of complaints that its Marmite ad trivialises the work of animal welfare agencies.
Some 400 complaints have been lodged by television viewers since the documentary-style spoof, which featured officials was screened on Monday evening.
The ad featured a team of welfare officers go into homes and reclaim "neglected" jars of Marmite from their owners.
A new Marmite advert in which a team of welfare officers go into homes and reclaim "neglected" jars of Marmite from their owners has triggered over 330 complaints to The Advertising Standards Agency (ASA) since it was first aired on Monday.
The ASA confirmed that it had received 330 complaints with viewers arguing that the advert was in "poor taste" and "deeply offensive".
A spokesman for the authority said: "The complainants say it is in poor taste while others maintain that it is deeply offensive. Some have objected that it trivialises the work of both animal welfare charities (RSPCA) and child protection agencies."
The ASA said complaints were still being monitored but stressed that no further action was currently being taken.
There was a mixed reaction to the advert on the company's Facebook page.
Some users complained that the advert was " trivialising cruelty", with one user labelling it "distasteful" and "inappropriate".