Russia’s ambassador told a crowded room of businessmen Friday that the most serious spy scandal between Canada and Russia in decades was not that big of a deal.

"With all due respect to Canada, it is not, believe me, the heart of our security concerns," Ambassador Georgiy Mamedov said in a speech at the Speakers Forum in Toronto.

He said the incident was not likely to damage bilateral relations and said both countries’ real concerns revolve around terrorism.

“What we are talking about is very marginal. It will die away,” Mamedov said.

On Wednesday, navy Sub-Lt. Jeffrey Paul Delisle admitted he had passed military secrets to Russia over a five year period in exchange for $3,000 a month.

Mamedov was in charge when Delisle walked into the Russian embassy in 2004 and offered to work as a spy, passing along secrets about Canada and its allies.

But he didn’t apologize. Instead he said people need to move on from their ideas about ‘spy novels’ from the Cold War.

So far the Canadian government has not publicly condemned Russia for the incident, though opposition MPs have called for Ottawa to get tough with the ambassador.

“You need to tell them when they've crossed the line that it's not appropriate,” Foreign Affairs Critic Paul Dewar has said.

But Public Safety Minister Vic Toews has declined, saying he doesn’t want to “jeopardize any proceedings.”

The government is remaining tight lipped about any exchanges between the two countries on the matter. CTV News first reported in January that several Russian diplomats had been expelled over the spying. But Ottawa has not acknowledged that, a move that makes no sense to one expert.

“It’s not a secret to the Russians. It's not a secret within the Canadian government,” national intelligence expert Wesley Wark told CTV News. “All they are doing is misleading the Canadian people about the gravity of the case.”

Since the breach, Canada has been working with U.S. intelligence services to tighten security around classified intelligence.

Delisle is set to be sentenced in January.