The first debate of the federal election season will take place in the depths of summer with the leaders of all four major national parties going head to head.

Prime Minister Stephen Harper, NDP Leader Tom Mulcair, Green party Leader Elizabeth May and — after some initial reluctance — Liberal Leader Justin Trudeau will take part in an Aug. 6 debate sponsored by Maclean's magazine.

Liberals had wanted the debate to include a live audience or questions from ordinary Canadians, but multiple sources say that idea was shot down by the Conservatives and NDP.

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The debate will be broadcast live on Toronto-based Citytv, CPAC and the multicultural Omni 1 and Omni 2 channels, as well as on each broadcaster's website, Facebook, YouTube and on Rogers Radio news stations.

Omni's coverage will be translated into Italian, Mandarin, Cantonese and Punjabi; CPAC's coverage will be in both French and English.

The debate is to be moderated by Maclean's political editor Paul Wells.