OTTAWA -- The chairman of the House of Commons transport committee says it is too early to reconvene this summer to discuss rail safety in light of the ongoing investigation in the Lac-Megantic disaster in Quebec.

Conservative MP Larry Miller says there may well come a time to examine whether Transport Canada policies and regulations played a part in the deadly train accident that claimed at least 20 lives with another 30 missing and presumed dead.

New Democrat MP Olivia Chow, a vice-chair of the committee, says all four NDP members on the committee have said they'd be willing to meet as early as next month.

But Miller said politicians need to get out of the way and let police and transportation safety investigators do their job.

"If there's something that points toward Transport Canada, of course we'll have to deal with that," he said of the Commons committee.

"But that's not clear at this point and it seems to be that there may have been negligence with the company. But again that's just initial thoughts that I'm just repeating what I'm hearing."

On Wednesday, Edward Burkhardt, president and CEO of U.S.-based Rail World Inc., which owns the runaway train, blamed the engineer for failing to set the hand brakes properly before the accident.

"He said he applied 11 hand brakes," Burkhardt said. "We think that's not true."

In the early hours of Saturday morning, the unmanned train -- all but one of its 73 cars laden with crude oil -- hurtled down a 11-kilometre incline, derailed and exploded in the centre of town.

Investigators are looking into a fire on the same train just hours before the disaster. A fire official has said the train's power was shut down as standard operating procedure, disabling the train's air brakes.

"The long and short of this is we need to let them conduct this (investigation) and we'll go forward from there," Miller said.

Chow said she doesn't want the committee to scrutinize details of the Lac-Megantic accident, but rather focus on the larger issue of Canadian safety regulations.

Daniel Paille, leader of the Bloc Quebecois, has also sent a letter to Prime Minister Stephen Harper requesting a special Commons committee meeting to examine rail safety, particularly the movement of dangerous goods in urban settings.

Miller flatly accused the Bloc of politicizing the tragedy and said he believes the NDP, which is heavily reliant on Quebec for 57 of its 75 seats, may be reacting to that political pressure.

"You don't just get together on an afternoon and come out of there with a (committee) resolution what we should do," said Miller.

"First of all, we don't know exactly what caused it, what should be done to make sure that it doesn't happen again. I think we need some more information before we even have a reason to get together."

The Ottawa meetings should be held no sooner than August, said Chow, who also wants to get a sense from local officials first whether a forum in Lac-Megantic would be useful for the community.

"Eventually the community will need some kind of forum where they could get the answers to their questions and get the rules and regulations clarified," she said.

"When that time would be, I don't know, but certainly not now."

Chow says potential witnesses could include the auditor general, and officials from Transport Canada and the Transportation Safety Board.

"I would ask the Transportation Safety Board to explain the various recommendations they've had in the past, and then ask Transport Canada why they're not doing them," said Chow.

In a 2011 report, the commissioner of the environment and sustainable development, inside the auditor general's office, pointed to long-standing weaknesses in the government's oversight of the transportation of dangerous goods.

Transport Canada was supposed to address all the recommendations by April this year, but has not yet met all of its commitments.

The Transportation Safety Board has been calling for mandatory voice recorders aboard trains for a decade, including last year after a Via Rail passenger train jumped the track in Burlington, Ont., killing three.

The TSB also recommended at the time the implementation of automatic braking systems, to avoid runaway trains.

David McGuinty, a Liberal co-chairman of the transport committee, did not respond to a request for comment.

With files from Bruce Cheadle