Asked on Tuesday whether having someone other than Mulcair as leader would change the dynamic in terms of a coalition between the two parties, Trudeau replied: "I don't know....Honestly, I don't want get into hypotheses. Maybe, but maybe not.
"There are no problems in terms of personality," he told The Canadian Press in an interview from Oakville, Ont. "Mr. Mulcair is a veteran politician who has proven himself.
"His style is anchored in the old way of practising politics. Politics needs to be about rallying. And we have very different perspectives on how politics should be practised."
Some recent polls have suggested the possibility of a minority government in Ottawa after this fall's election.
Mulcair reiterated his openness last month to a possible coalition with the Liberals if it is necessary to topple Stephen Harper's Conservatives.
The Opposition leader accused Trudeau at the time of putting personal interests ahead of those of Canadians because the Liberal leader had repeatedly expressed his lack of interest in discussing coalitions.
"Whenever we have opened that door, Justin Trudeau slams it shut,'' Mulcair said. "My first priority is to get rid of Stephen Harper. The first priority of Justin Trudeau is Justin Trudeau.''
On Tuesday, Trudeau categorically rejected the idea of a coalition.
"I'm not interested at all in any formal arrangement," said the Liberal leader. "On the contrary, I find that wanting to make arrangements with other parties is putting the desire for power ahead of the interests of Canadians. What Canadians are interested in is having a coherent government."
Trudeau noted that the two parties have major differences of opinion on economic and constitutional issues.
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