European Union members are called on to choose low-carbon fuels over more polluting ones like oil sands under new fuel rules, a commissioner said Tuesday.

A proposal Tuesday from the European Commission calls on regional refiners to report carbon emissions from feedstocks rather than list so-called oil sands as more carbon intensive than other types of crude oil.

The proposed directive, however, retains a provision for calculating carbon intensity of different fuel types over their life cycle.

"It is no secret that our initial proposal could not go through due to resistance faced in some member states," European Climate Commissioner Connie Hedegaard said in a statement.

European leaders in September met in Ottawa with Canadian Prime Minister Stephen Harper and trade representatives to discuss comprehensive economic and trade agreements.

Harper's administration is seeking to diversify an oil export economy that relies almost exclusively on the United States. Last year, the Canadian government said European emissions standards on the heavier grade of crude oil found in Canada were "unscientific and discriminatory."

The European Commission said the proposal maintains a requirement to reduce greenhouse gas emissions from fuels by 6 percent by 2020. Any increase in the volume of oil sands in the European market needs to be offset elsewhere, the commission said.