All evidence still points to the Keystone XL pipeline being approved, despite the political storm raging over it in Washington, D.C., Canada's natural resources minister says.

Greg Rickford told a press conference in the American capital today that he thinks, based on U.S. State Department recommendations, the project makes sense and will go ahead. 

"Prime Minister [Stephen] Harper and myself believe it is a question of when, not if... and every piece of evidence is [this is] the right decision, so that I think it has given us confidence based on science and facts that at some point this project will be approved,"​ Rickford told reporters at the Canadian embassy.

Rickford said it's important to separate the State Department report that found there would be no adverse effect on the environment from the complicated political process now playing out in Washington.

Supporters and critics of the pipeline are battling it out in Congress.

"This is a debate between the U.S. president and the American people," Rickford said. 

1 hurdle passed

Rickford has been meeting with his U.S. counterpart and senators on cross-border energy policy and the controversial proposed pipeline.

The cross-border pipeline to carry Canadian oilsands bitumen from Alberta to Texas for processing and possible export is at the centre of a heated battle between Congress and President Barack Obama.

The House has passed a bill approving the pipeline, and it has cleared one hurdle in the Senate. A final Senate vote on the pipeline will be held before Obama's Jan. 20 state of the union address.

Obama's office has said he will veto the bill, saying the State Department has a process to follow on whether to allow the pipeline to go ahead.

Critics of the project point out that Obama has been very public with his doubts about the pipeline that would carry about 800,000 barrels of heavy Alberta bitumen to the U.S. Gulf Coast every day.

"Anyone who is paying attention to the actual process would realize that President Obama has expressed deep skepticism," said Danielle Droitsch, director of the Canada program with Natural Resources Defence Council in Washington. "In his numerous statements over the past several months, he has questioned the national interest of the project whether it be either about jobs or export, and certainly expressed concern about climate and the risk of pipeline spills."

Opponents argue the pipeline will spur increased oil production in Alberta and lead to a rise in greenhouse gas emissions. Droitsch thinks that the Canadian government is now trying to put a positive spin on what is becoming a not-so-positive outlook for the project.

"They have to find a way to look at the presidential veto threat and somehow spin it into something that might work for Canada. But the reality is that President Obama has already clearly stated his questions and criticism of the project itself."

One issue was resolved last week, when a court challenge in Nebraska failed to overturn the state's decision to allow the pipeline route through its territory.

An Obama veto of the pipeline project could be overcome by a so-called "super majority" of 67 U.S. senators. The Keystone XL bill cleared its first hurdle in the Senate this week with 63 votes in favour and 32 opposed.