Canadian pipeline company TransCanada wants to build Keystone XL to supplement its existing pipeline carrying tar sands oil from Alberta. The current network terminates in Oklahoma and Illinois and the extension would end along the Gulf of Mexico.
The U.S. State Department needs to approve the project because the pipeline crosses the Canadian border.
Canadian Natural Resources Minister Joe Oliver said following meetings with U.S. Energy Secretary Steven Chu and members of a U.S. House of Representatives energy committee that he felt Washington recognized the importance of the project.
"We remain optimistic that the government understands that this is a very important project for the United States to provide secure energy from a reliable friend and partner," he was quoted by the Platts news service as saying.
Keystone XL would send roughly 15 million barrels of oil to the United States every month. Critics of the project point to the number of spills on the existing Keystone oil pipeline and the potential environmental impact of heavy crude oil from tar sands projects in Alberta.
"In absolute terms, total oil sand emissions are equivalent to emissions from coal-fired electricity generation in Wisconsin," said Oliver.