In a sign that Independent senators are continuing to assert that independence, some in the Red Chamber are attempting to force the government to split off the infrastructure bank from the budget implementation bill, threatening to delay not only the creation of the bank but the government's budget plans.

Independent Quebec Senator André Pratte, one of Prime Minister Justin Trudeau's first Senate appointees, introduced a motion in the upper house Tuesday that would remove the bank from Bill C-44, the budget bill, in order to allow further study in the fall.

The proposal, the latest example of the Senate defying the will of the Trudeau government, is strongly opposed by Finance Minister Bill Morneau, who has said the bank is integral to ambitious infrastructure spending plans.

While the government, and its point man in the Senate, Peter Harder, might be opposed to the move, Pratte said he is comfortable he has enough votes from his fellow Independents, and some Liberal and Conservative senators, to split the bill. Debate on the motion will begin tomorrow.

Prime Minister Justin Trudeau shrugged off the motion Tuesday.

Trudeau on the Senate 1:30

"Obviously, I'm not going to speculate on what might happen, what could happen. We're proud we have a newly independent, less-partisan Senate that is taking a responsible and serious look at what is put forward by the House of Commons. We'll always listen."

In an interview with CBC News, Pratte said he has serious concerns about the bank and the risk it would pose to taxpayers. "The government fails to give clear answers to what the risk level will be," he said, adding Morneau hasn't been clear on just how much initial money will be pumped into the $35-billion federal fund intended to help build projects through public-private partnerships across the country.

A recent appearance by Morneau before the Senate's banking committee was confusing and simply prompted more questions, Pratte said.

"That absolutely needs to be clarified before we give the green light," he said.

Critics argue the bank will lead to more user fees, higher tolls and the prospect that Canadians will be left on the hook if projects such as bridges and light-rail lines don't provide the kind of returns investors had expected. Infrastructure Minister Amerjeet Sohi has insisted that will not be the case.

Project details exempt from Access to Information

Pratte, a former journalist with La Presse, is also raising red flags about wording in the legislation that would shield the bank's projects from federal Access to Information law, as private companies could deem that information "privileged," making it difficult for the public and the media to scrutinize a particular project. Pratte said this is untenable.

The proposed governance structure would also give federal cabinet the powers to fire the bank's CEO and senior leadership at will. "This raises the concern that politicians will get involved in the daily business of the bank. For private partners, this is worrisome, and that's why there needs to be an in-depth study. This is why we need more scrutiny.

"We need to set up the bank in a more independent fashion."

Minister of Finance Bill Morneau is greeted by Senator Larry Smith, right, as he appears at a national finance Senate committee. Morneau is opposed to separating the infrastructure bank from the budget bill. (Justin Tang/Canadian Press)

Lastly, Pratte is concerned the bill treads on provincial jurisdiction, pointing to wording in the legislation that would allow the bank to be deemed an "agent of the Crown," allowing some projects to be exempt from provincial laws and/or municipal regulations.

The Quebec senator conceded the government has said it would not do such a thing, but he is still worried the clause could be exploited by future governments.

"All relevant provincial and territorial laws will apply for all projects in which the bank invests. There are no special exemptions for the bank or for bank projects. We have sought counsel on this, and that is absolutely clear," Morneau told senators late last month.

Time ticking ahead of summer break

Pratte said the Senate and the committees tasked with studying the bill will have only a few sitting days to sift through a 300-page budget before Parliament rises for the summer break. "These are complex questions that you cannot solve or find solutions to in a few hours at committee, you need more time. I don't think delaying the creation of the bank by a couple of months will have a major impact on infrastructure expenditures."

(Some Senate committees have been conducting pre-studies of the budget, and many senators have expressed similar concerns with the infrastructure bank.)

A spokesperson for Morneau told CBC News Tuesday that while "the Senate has an important role to play in the legislative process … C-44 is our budget plan. Its goal is to create good middle-class jobs, dynamic communities and a resilient economy. We will continue to work with the Senate and pass this bill which will help Canadians across the country."

"The minister was pleased to appear at [committee] to discuss key elements of the bill in detail, and senators agreed that his testimony contributed to their understanding of our plan."

The government could also challenge the motion on the grounds that the Senate does not have the right to alter a spending bill, which could prompt the Speaker to rule on whether Pratte's move is out of order. Pratte said Tuesday he believes a motion to divide the bill is well within the rules.