Organizers of a debate on women's issues say the event won't go ahead as planned because the Conservative and NDP leaders won't participate.
The debate, scheduled for Sept. 21, had originally been envisioned as a live broadcast debate with all five major party leaders.
But a spokeswoman for Up for Debate, a coalition of dozens of women's groups and other organizations, says that has now been cancelled because Stephen Harper — and therefore Tom Mulcair — won't participate.
Mulcair has said he won't take part in any leaders' debates without Harper, and the party says it told organizers it wouldn't make sense for Mulcair to take part without the prime minister.
The NDP says Mulcair was the first of the major party leaders to agree in principle to the debate and has been working with Up for Debate, looking for other ways to highlight women's issues through the campaign.
They included a town hall, a one-on-one interview event, or sending status of women critics.
Debate spokeswoman Melanie Gallant says organizers are now looking into doing one-on-one interviews with the leaders and releasing the videos of those interviews at an event on the date the debate would have gone ahead.
The NDP says Mulcair would take part in that process "enthusiastically and with pride."
The five main party leaders will take part in a French-language debate Sept. 24 at the Radio-Canada studios in Montreal.
The three major party leaders will also debate foreign affairs issues in the Munk Debates Sept. 28.
Harper, for his part, has rejected the traditional debates run by a consortium of the major broadcasters. He has also agreed to a Sept. 17 Calgary debate sponsored by the Globe and Mail and Google Canada and a French-language debate on Quebec's TVA network on Oct. 2.