The director the Canadian Security Intelligence Service is downplaying his comments that provincial cabinet ministers and bureaucrats are being controlled by foreign governments.

Richard Fadden issued a statement on Wednesday to help put his allegations "in context."

"The Service has been investigating and reporting on such threats for many years," he wrote. "Foreign interference is a common occurrence in many countries around the world and has been for decades."

CSIS did not inform the Privy Council Office or provincial authorities because the cases are not considered "of sufficient concern."

"There will be no further comments on these operational matters" by CSIS, he concludes.

Fadden did not name the cabinet ministers during his comments to an interviewer Tuesday, nor did he indicate which province each works for.

But they have not concealed their involvement with the foreign governments in question, he said, hinting that China may be involved. And there are signs that the ministers may be changing public policy as a result.

CSIS also suspects that several members of B.C.'s public service are similarly being swayed by foreign governments, he said.

The Prime Minister's Office had "no knowledge" of the allegations, Harper's spokesperson Dimitry Soudas said on Wednesday.

B.C. Premier Gordon Campbell declined to comment on the matter. But Ontario Premier Dalton McGuinty asked that more details be released regarding the agency's suspicions.

"I think, in fairness, what Canadians are owed right now is more information," McGuinty said. "If there are some real concerns, let's find out exactly what those are and let's find a way to address them."

Security analysts have asked why the agency chose to comment on the matter before contacting the relevant provincial governments.

Meanwhile China's President Hu Jintao is set to meet with Prime Minister Stephen Harper on Thursday in Ottawa, two days before the G20 summit gets underway in Toronto this weekend.

The Chinese government has not commented on the allegations.

Fadden said five or more countries are quietly enlisting potential politicians at Canadian universities, some of whom belong to their country's diaspora.

Former CSIS agent Michel Juneau-Katsuya said it can be difficult to distinguish between legitimate persuasion of foreign officials, and espionage.

"The problem is we're operating in a grey zone. It's totally legal -- and Canada does it -- to send diplomats abroad and positively influence foreign officials in order that they do business with us, or something like this," he told Canada AM.

"Where it falls into espionage activities is when they systematically employ their national intelligence services to aggressively target and pursue certain individuals."

With files from The Canadian Press