Liberal Leader Justin Trudeau says a proposed west-east pipeline project will not go forward unless it addresses key environmental concerns.

Calgary-based TransCanada Corp. is in the process of lining up potential producers who would use the proposed pipeline, which would run from Alberta to New Brunswick.

The federal Liberal leader told the CBC’s Information Morning Fredericton on Thursday he has specific questions about potential toxins that may be used in the pipeline.

"I think it is a proposal that is extremely interesting. We are waiting to look at how they are going to deal with both the community, local, aboriginal concerns and the environmental concerns," Trudeau said.

Premier David Alward said federal Liberal Leader Justin Trudeau sent a bad message to the rest of Canada with his pipeline comments. (CBC)

"The [substance] that they put to make that thick crude, thick bitumen run through those pipes can be very toxic. I want to see the plan for being environmentally responsible on it because it won’t go ahead if it will cost us on pollution, in degradation and in inefficiencies in the coming years."

The pipeline project has won widespread support from political leaders in New Brunswick. Trudeau's comments created a stir in question period in Fredericton on Thursday.

Premier David Alward said Trudeau's comments "sent a bad message to the rest of Canada."

He called on provincial Liberal Leader Brian Gallant to ask Trudeau to clarify his remarks about the proposed pipeline project.

'Disappointing to say the least'

"So where does the leader of the opposition of New Brunswick stand, does he support the people of New Brunswick and jobs in New Brunswick, so our young people can work here, or does he support the Liberal Party of Canada?" Alward said.

Gallant tried to counter Alward's attack by expressing his party's support for the project.

"It is something we support whole-heartedly," Gallant said.

Energy Minister Craig Leonard also called on Gallant to demand Trudeau immediately clarify his remarks.

He said political uncertainty over an infrastructure project this important to the province is not good.

"There are investors who are looking for certainty on the political side. We have provided that from our provincial government. It was a big issue when we were able to say the provincial legislature supported the project unanimously," Leonard said.

"Any time you have a statement of non-support that is never a positive thing. I won’t speculate on the impact it would have on the overall project. We are trying to build on the positive economic development benefits and the pipeline would have a huge impact on our province and to have the federal leader of the Liberal Party to be non-commital is disappointing to say the least."

Leonard said any concerns raised by Trudeau about the environment would be addressed during the regulatory phase of the project and any environmental impact assessments.

Politicians lobby for pipeline

Premier David Alward travelled to Calgary in February to lobby Alberta politicians and oil patch executives on the project. Provincial Liberal Leader Brian Gallant has also endorsed the pipeline.

Saint John Mayor Mel Norton followed in the premier’s footsteps and made his own trip to Calgary to express his support for the pipeline project.

Federal Natural Resources Minister Joe Oliver said in December, months before TransCanada announced its proposal, the west-east pipeline project would be of national interest during a trip to Saint John.

Officials with Irving Oil Ltd. have indicated the company’s Saint John-based refinery, which is the largest in Canada, could handle western crude oil.

The New Brunswick government has estimated the pipeline project has the possibility of creating 2,000 jobs during the construction phase and a few hundred refinery jobs afterward.

TransCanada has said if the next phase is successful, the pipeline company plans to start seeking regulatory approvals later in 2013, and the oil could start flowing to Eastern Canada by late 2017.

The proposal would be to convert 3,000 kilometres of the company's natural gas pipelines to allow for crude oil to be transported. The company would also be looking at building 1,400 kilometres of new pipeline from Quebec into Saint John.