OTTAWA -- Russian spies don't consider Canada a prime target, and they learned nothing of value from a junior Canadian navy officer who passed them classified intelligence for four years, says Moscow's outgoing envoy to Ottawa.

Russian Ambassador Georgiy Mamedov said he never took disgraced Canadian Jeffrey Delisle seriously when he started selling Western military secrets to Russia in 2007.

"To put it bluntly, it was never a major concern to me or to Moscow," Mamedov said in an interview with The Canadian Press, during which he answered several questions for the first time about the recent Canadian spy scandal.

"It was never antagonistic or an aggressive intent to do something. To use a vulgar expression, we never fished."

Mamedov said spying is "the game that everybody's involved in," but Canada has not been a very busy playing field for Russian espionage.

"So you're not at the centre of our concern," he said. "There are other countries that are probably more tempting targets for our intelligence, like we are a more tempting target for their intelligence."

Delisle, 43, was sentenced to 20 years in prison last year after pleading guilty to regularly passing classified western intelligence to Russia in exchange for cash over a four-year period.

Delisle approached Russia to offer his services while he was going through a period of emotional turmoil; his marriage had broken up and he was going through financial difficulties.

The case raised serious security questions, including whether shared intelligence from Canada's allies -- notably the United States -- had fallen into Russian hands.

Delisle's spying was discovered at the military's Trinity intelligence centre in Halifax, and he worked at other sensitive posts, including the directorate of defence intelligence in Ottawa.

Delisle copied top-secret information on a small USB drive and was able to effortlessly remove it from a secure building in Halifax.

He wasn't caught until 2011 when the U.S. Federal Bureau of Investigation tipped off the Canadian Security Intelligence Service, Canada's spy agency.

But as far as Mamedov is concerned, the whole affair amounted to very little in the grand scheme of broader Russian spying activities over the years.

"Russia gained nothing whatsoever," he said. "If you ask your special services, they will say it was mostly their problem and not our adventure."

Few diplomats will discuss intelligence matters, but Mamedov candidly answered several questions about the Delisle case. The envoy is retiring from the Russian foreign service and is leaving Ottawa after an 11-year posting, one of the longest by a foreign diplomat in Canada's capital.

Before coming to Canada, Mamedov was Russia's deputy minister of foreign affairs, and led his country's nuclear arms reduction talks with the United States.

"Over the years, when I was deputy foreign minister in charge of relations with the United States, Canada, NATO, arms control, I was involved in very delicate negotiations. And of course, like my western counterparts, to some extent I relied on intelligence information," he said.

"This is the nature of arms control negotiations. And I couldn't remember a single instance when I used intelligence information gathered in Canada."

Over the years, he said, Canada and Russia have developed a good intelligence sharing relationship, notwithstanding the current chill in relations over Canada's angry disapproval of Russia's annexation of Crimea and the current unrest by pro-Russian separatists in eastern Ukraine.

Mamedov characterized the Delisle affair as a distracting sideshow from the more serious intelligence-sharing operations that he said keeps countries safe from terrorist attacks, and other threats.

In the past, Russia has shared intelligence with Canada that helped save the lives of its soldiers in Afghanistan, he said.

And he said Russia exchanged valuable intelligence in the run-up to the Sochi Winter Olympics that his country hosted in February.

"Every time something happens like Delisle or some other artificial crisis, it makes me feel we are losing time," Mamedov said.

He said much more is gained by "real professional co-operation" that helps countries battle terrorism or deal with threats from weapons of mass destruction than "one guy crossing the line," such as Delisle.

"It happens to our people, it happens to your people," he added.

The Harper government has been a vociferous critic of Russia lately over the Ukraine crisis.

But on the Delisle affair, the government took a much softer diplomatic approach, saying almost nothing publicly that could be seen as disparaging of Russia.