The European Commission opted to classify tar sands as 25 percent more polluting than conventional crude oil. Suppliers would need to invest in green energy products to offset pollution from tar sands to import that type of oil under the new European rules.
The International Energy Agency ranks Canada third behind Saudi Arabia and Venezuela in terms of oil reserves. The vast majority of that oil is found in so-called tar sands oil in Alberta province.
Canadian Natural Resources Minister Joe Oliver, in a letter to his European counterpart Gunther Oettinger, said that there wasn't comprehensive data backing Europe's claims. Any measure that treats tar sands oil differently than conventional crude, he added, "is discriminatory and potentially violates the European Union's international trade obligations."
Europe's climate Commissioner Connie Hedegaard had to counter an opposing opinion from Oettinger on the issue.
Europe doesn't get much of its crude from Canada. Nevertheless, Oliver argued Canada was being treated unfairly, noting the Canadian energy industry tends to be more transparent about emissions from oil sands than other countries.
If the "discriminatory measures" are put in place, he added, "Canada will not hesitate to defend its interests."
2014: The Year in Music [PHOTOS]