OTTAWA - The Canada Revenue Agency has uncovered at least $33 million in undeclared income from Canadians feeling the heat over their offshore accounts with two Swiss banks.

A spokesman for the federal taxman told The Canadian Press Tuesday that 19 people with accounts at the HSBC Private Bank in Geneva have come forward since news of a major leak of banking information recently emerged.

Of that small initial group, 15 investigations have revealed $1 million in unreported income as of Oct. 3.

That's only the tip of the iceberg.

Ottawa is examining information on 1,800 Canadian HSBC account holders. They were part of a larger list of about 80,000 accounts that a former HSBC bank IT security specialist passed on to French investigators.

According to reports, there were 8,000 accounts on the list that belonged to French citizens, and only two accounts had been declared for tax purposes. France gave its citizens a chance to pay up without facing penalty and half a billion euros were returned

Information that came to light last year on Canadian accounts at another Swiss bank, UBS, has turned up $32 million in unreported income from 124 audited files. The agency is still plowing through the accounts of at least another 83 Canadians who had come forward.

Prime Minister Stephen Harper is expected to keep up the pressure for more transparency and disclosure when he visits Switzerland later this week.

Revenue Minister Keith Ashfield said in an interview Tuesday that his department expects to double the number of voluntary disclosures on offshore funds this year.

The revenue agency said that in 2009 it had found more than $1 billion in federal taxes owed by Canadian taxpayers hiding assets abroad.

Another $138 million was recouped from 3,000 Canadians who came forward of their own accord.

"We're probably looking at doubling the voluntary disclosures this year," Ashfield said. "We're being very proactive on the file and things are happening."

The United States and Germany have been at the forefront of a pressure campaign to force more transparency in the Swiss banking system.

The Canadian government found out indirectly that Canadians might be hiding money through Swiss bank UBS when Washington threatened a lawsuit against the institution if it did not hand over details of American tax evaders.

Canada has a tax treaty with Switzerland that allows for an exchange of information, but some evidence of wrongdoing must first be presented.

Officials say Harper will discuss the issue with Swiss President Doris Leuthard when the two meet this Friday in Bern. Switzerland is host of the biennial summit of francophone nations this weekend in Montreux.

Jack Mintz, director of the University of Calgary's School of Public Policy, says Swiss banks have a big presence in Canada's financial community.

"Switzerland is one of the major countries that we borrow from, they play a significant role here in financing Canadian investments," said Mintz.

Ashfield said he could not comment on where Canada's talks with Switzerland stand.

"We're working with a number of different countries to come to an agreement on financial records that they may be holding in those countries," said Ashfield.

"We're looking at initiatives in that fashion that we could move forward overall. It's almost like a contractual agreement with those countries to release information back and forth."

Ashfield's predecessor Jean-Pierre Blackburn had pushed for changes with the Finance Department to make it easier for the tax agency to obtain intelligence gathered about Canadians with questionable banking activities overseas. Those changes have still not been made.