Liberal Leader Justin Trudeau is signalling the tax cuts promised by the Conservative government could lead to a political showdown ahead of the 2015 federal election.

Trudeau suggested in an interview today with CBC's French-language service Radio-Canada that a Liberal government would prioritize investment in infrastructure, education, and research over any tax relief.

He says he's made a promise as leader of the party to build an economy with a strong and growing middle class.

Trudeau made the comments in response to a question on Radio-Canada's Les coulisses du pouvoir about the cost of those planned investments, and whether it would be politically difficult for him to reverse any cuts given to taxpayers.

Finance Minister Joe Oliver hinted last week cuts could be announced as soon as the annual fall economic update.

Oliver has said plans to balance the budget in 2015 remain on track despite the falling price of oil.