Canada, host to what organizers bill as the largest global gathering on AIDS and HIV, has not taken seriously its avowed effort to help defeat the pandemic, a top AIDS advocate said on Wednesday.

U.N. envoy Stephen Lewis urged Canada to follow through on legislation passed in 2004 that allowed the export of low-cost generic medicines to developing countries.

“I feel almost personally duped ... I actually believed with a kind of charming innocence that the governments of Canada - Liberal and Conservative - would really take this act seriously,” Lewis, a Canadian, told a news conference ahead of the International AIDS Conference in Toronto.

“All it takes, and it could be done this week, is for the government of Canada to issue a compulsory license for the manufacture and export of generic drugs.”

Canada has a number of generic drug manufacturers, and while one of them, privately held Apotex Inc, has made a generic version of an AIDS drug, there have been no exports, the news conference organizers said.

The AIDS conference, which starts on Sunday, is expected to draw some 20,000 participants to Canada’s largest city for a week of events including films, fashion shows and seminars and scientific discussions about AIDS.

Speakers will include Bill and Melinda Gates, whose foundation on Wednesday pledged $500 million over five years to the Global Fund to fight AIDS, TB and Malaria - the largest private donation the fund has ever received.

Figures from the U.N. population fund estimate that 38.6 million people were living with HIV/AIDS last year. The 2005 AIDS death toll was 3.1 million.