However, the company says it wasn't singling out those countries for allegedly producing less ethical oil than the Alberta oilsands.
An Enbridge executive presented the illustration at an aboriginal business conference in Calgary in November of 2010 on a slide with the subheading "Who would you prefer to buy your oil from?"
It shows two old-fashioned gas pumps sitting side-by-side. One gas pump, named "Alberta Canada," shows a pair of wide-open cartoon eyes peering out from just below the face of the pump.
A second pump shows scowling, angry eyes with furrowed eyebrows and dark stress lines underneath the eye sockets.
Inscribed on that pump in overlaying text are the names of several Persian Gulf countries: the United Arab Emirates, Saudia Arabia, Kuwait and what appears to be Bahrain, as well as a question mark.
The cartoon slide came at the end of a presentation by Andy Popko, at the time Enbridge's vice-president for aboriginal relations, which outlined economic opportunities in the Northern Gateway project for aboriginal communities and businesses.
Though Enbridge executives have said in speeches that oilsands crude is "ethically developed," the company has not publicly compared the ethics of oil produced by Alberta with other spots around the world.
A company spokesman denied the presentation shows Enbridge endorsing the view that Gulf countries are unethical places to import oil from.
Enbridge Northern Gateway spokesman Paul Stanway said Popko put the countries in his Canadian Council for Aboriginal Business conference presentation to show how other people were making the argument.
Stanway said Popko was only outlining Enbridge's support for the "general concept" of the argument, and not singling out specific places for being allegedly unethical.
"All I can confirm is that he was responding to interest in what was an issue at the time with regard to ethical oil," Stanway said in an interview, noting that Enbridge was regularly asked about the topic in the fall of 2010.
"Those countries have been raised by other people," he said.
"So Mr. Popko expressed our point of view, which was that yes, we support the general concept that Alberta oil, that Canadian oil is produced to higher standards than that produced in other places in the world."
He said those standards include human rights and environmental protections.
When asked if those other places include Middle Eastern states, Stanway said: "Many parts of the world. You pick your spot. We don't make any direct comparisons."
He added: "We're a transporter of energy. We don't deal with international affairs. This is not our business."
The crux of the ethical oil argument is that oil bought from some countries - such as those in the Middle East and other places like Russia and Venezuela - is unethical because energy revenues go to governments that squelch human rights, suppress women and feed terrorism and armed conflict.
The Alberta oilsands has none of those alleged problems, the argument holds.
It claims that as an "ethical" energy source, the oilsands should be expanded and given preference in foreign markets - including the U.S. - as well as in Canada over allegedly unethical oil imports.
Greenpeace climate and energy campaigner Keith Stewart said in his view the slides clearly show Enbridge calling the Persian Gulf countries "unethical" suppliers, adding the company is being "disingenuous" and contradicting itself in the ethical oil debate.
"They're saying one thing in public and one thing privately. And when a reporter calls them about this they back away from the harder-line stance."
"These are their words and they're using this whole 'ethical oil' argument to try and sell people on their (Northern Gateway) pipeline" as it undergoes a regulatory review, he said.
A booming oilsands sector is vital for Enbridge's proposed Northern Gateway pipeline, which would carry extracted bitumen 1,170 km from near Edmonton, Alta., to an export terminal on the B.C. coast, with some of the oil set to be shipped to refineries in China.
The Northern Gateway project has been hotly opposed by environmental and aboriginal groups, who charge the pipeline and related coastal oil tanker traffic would result in spills devastating ecologically sensitive marine and forest areas.
Enbridge's environmental track record came under fresh criticism this week with the release of a scathing report from a U.S. regulator saying Enbridge was slow to respond to a 2010 Michigan pipeline spill, and did nothing when first warned of a defect with the pipeline five years earlier.
Enbridge has said employees involved at the time of the spill were "trying to do the right thing" and that "a series of unfortunate events and circumstances resulted in an outcome no one wanted.''
The company has said it is committed to learning from the Michigan spill to ensure something similar never happens again.
The Enbridge slides were later sent to Aboriginal Affairs and Northern Development Canada, records obtained by The Canadian Press through Access to Information show. They were also uploaded to the aboriginal business group's website but not publicly linked to.
The ethical oil argument was popularized in a 2010 book by conservative activist and journalist Ezra Levant. It currently features in ongoing media and advertising campaigns by the online group EthicalOil.org and has also been used by the Harper government in its defense of the oilsands.
Stewart said the debate offers a false choice, and that what he called the negative environmental impact of oilsands development and the Northern Gateway pipeline cuts claims of ethical superiority off at the knees.
"They set up a straw man, which is 'since we need more oil where should we get it from?' when the reality is we have a choice to reduce the demand for oil."
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