A long-delayed environmental report from the U.S. State Department could remove a major hurdle for a controversial oil pipeline from Canada to the Texas Gulf Coast.

A new State Department report on the proposed Keystone XL oil pipeline finds that the project would have a minimal impact on the environment, an assessment likely to increase pressure on the White House to approve it. But the report sets no deadline for doing so.

Given this evaluation of environmental impact, President Barack Obama and his administration will face increased pressure to approve the project, which enjoys widespread support among Republicans, and some measure of support among Democrats and allies of the administration, like labor unions.

The proposed pipeline would carry crude derived from oil sands in Canada to refineries in the United States.

"Our national interest will be served only if this project does not significantly exacerbate the problem of carbon pollution,” Obama said in June 2013. “The net effects of the pipeline's impact on our climate will be absolutely critical to determining whether this project is allowed to go forward."

The findings by the new State Department report could hasten a decision by the administration, though there is no hard and fast deadline by which Obama or Secretary of State John Kerry must act. The evaluation fell to the State Department because the proposed $7 billion project by TransCanada Corp would cross the U.S.-Canada border.

Quickly after the report's release, lawmakers ratcheted up pressure on Obama to act.

"Mr. President, no more stalling– no more excuses," said Senate Minority Leader Mitch McConnell, R-Ky. "Please pick up that pen you’ve been talking so much about and make this happen. Americans need these jobs."

Centrist Democrats like West Virginia Sen. Joe Manchin hailed the findings, as well.

"I have been incredibly frustrated for more than five years by the repeated and unnecessary delays in moving forward with the construction of the Keystone XL Pipeline," he said. "I am pleased the State Department has confirmed there is no evidence of any negative environmental impact from building this pipeline."

In a statement Friday night, White House spokesman Matt Lehrich said the information would be "closely evaluated by Secretary Kerry and other relevant agency heads in the weeks ahead. A decision on whether the project is in the national interest will be made only after careful consideration of the (impact statement) and other pertinent information, comments from the public, and views of other agency heads."

Nathan Vanderklippe/Globe & Mail / Reuters Pipes for underground fuel transport for TransCanada Corp.'s Keystone XL pipeline lie in a field in Gascoyne, North Dakota April 23, 2013.

Environmentally minded Democrats said the report paid insufficient attention to the environmental impacts of extracting the oil in the first place.

"I will not be satisfied with any analysis that does not accurately document what is really happening on the ground when it comes to the extraction, transport, refining, and waste disposal of dirty, filthy tar sands oil," said Sen. Barbara Boxer, D-Calif., chairwoman of the Senate panel that oversees environmental issues.

Kerry said earlier in January that he hoped to move along with his own consideration of the process quickly, though he signaled that he doesn’t feel pressure to move before various analyses are complete.

“We are doing it, and I can promise our friends in Canada that all the appropriate effort is being put into trying to get this done effectively and rapidly,” Kerry said Jan. 17 during an appearance with his Canadian counterpart. “And my hope is that, before long, that analysis will be available, and then my work begins.”

Protesters rally about the Keystone XL oil pipeline along U.S. President Barack Obama's motorcade as he arrives at the Jefferson Hotel in Washington July 11, 2013.

Following the release of Friday’s report, what’s known as a “comment period” will take place; a comment period allow both government agencies and the public as a whole to offer their input about a proposed rule or regulation. The Keystone report will open up a 30-day comment period for the public, and a comment period for relevant government agencies of up to 90 days.

“I'd stress, this is only one factor in a determination that will weigh many other factors as well,” State Department spokeswoman Marie Harf said at a briefing on Friday. “And for Secretary Kerry, climate and environmental priorities will of course be part of his decision making, as will a range of other issues.”

The project could also conceivably figure into political considerations for Obama. Republicans in Congress have long demanded his approval for the project. Free of major environmental objections to it, the president could conceivably extract a desired vote or policy from GOP lawmakers in exchange for giving construction of the pipeline a green light.

NBC News' Peter Alexander contributed to this report.