With a federal election scheduled for October, it is not clear what will happen to the plan, in the works since 2010, which was meant to bring in line with international safety standards.

"We should be talking about implementation right now," said , president of the 's Canadian board. "We are extremely, extremely disappointed."

Transport said it determined that the new rules would have more of an impact on smaller operators: "The introduction of the proposed changes in two phases would give smaller carriers more time to make the operational changes needed to meet the requirements."

, president of the Air Transport Association of , was pleased with what he sees as a change of course from Transport . He said the draft proposal had been too heavily influenced by pilots' unions.

McKenna, whose members include most Canadian airlines, but not top carriers Air or Airlines, said his group lobbied Transport Minister after the draft was published, saying new rules could raise operating costs by up to 30 percent.