The National Energy Board, in a letter to Enbridge, said it was imposing the deadline to meet national laws and budgets enacted this year by Prime Minister Stephen Harper.
"The Minister of the Environment and the NEB have jointly established the time limits for the submission of the environmental assessment and recommendation report," the letter read.
Enbridge aims to build the $6 billion Northern Gateway pipeline from oil sands projects in Alberta to ports in British Columbia and delivery to Asian markets.
Some residents along the western Canadian coast have protested against the project. British Columbia Premier Christy Clark last month listed demands on Enbridge. She stressed the need for "world-leading" oil spill response systems, respect for aboriginal rights and a stake in the economic benefits that represents the nature of the risk to the province.
Critics consider Alberta crude a considerable threat to the environment.
The safety record for Enbridge was tarnished by the 2010 oil spill in Michigan and a July oil spill on the same network in Wisconsin.
Enbridge said pipeline safety is its top priority.