WASHINGTON - The Obama administration is delaying a decision on the Keystone XL pipeline to gain clarity on the pipeline's proposed route through Nebraska and allow more time for comment from other government agencies.

In February, a state district court in Nebraska invalidated the route that had been proposed through the state . The State Department told representatives from congressional offices on Friday that they are extending the time period for agency comment until there is more certainty on the route.

There were supposed to be 14 days left in the agency comment period -- a 90-day period that started with the release of the final environmental analysis at the end of January . Given the continued uncertainty about the route, State said it will give agencies at least those additional 14 days once there is a decision on the Nebraska route.

The State Department said it is is reviewing the 2.5 million public comments that it has received. The extension announced Friday applies only to agency comments, however.

In a call with reporters Friday, a senior State Department official speaking on background said that, because the route through Nebraska may change, "the prudent decision was to allow additional time."

The department, the official said, "felt that it is important to have additional information and a better understanding of what that route might be, because it could have implications for the environmental, cultural and socioeconomic impacts that are being evaluated by the agencies."

The official noted that the route is "central to the environmental analysis of the project." If Nebraska decides to significantly change the approved route, that may require additional analysis and comment. If there is not a significant change, however, the official said, "there would not be a need for another public comment period around that route."

The official emphasized that the agency is continuing its evaluation of other aspects of the pipeline decision, despite the delay on the Nebraska route. "We are moving ahead very diligently with all other aspects of the review that are necessary for the national interest determination," said the official.

The announcement likely means that there will not be a decision on whether to approve or deny the pipeline until after the November 2014 elections. Nebraska is appealing the district court decision, which threw out a state law that gave decision-making power on the pipeline route to the governor, and would have allowed TransCanada to declare eminent domain over land in the proposed path. Anti-Keystone activists in Nebraska say there likely won't be a state Supreme Court decision on the issue until January 2015 or so.

Anti-Keystone activists praised State's move to delay the decision. "The basic fact that Nebraska has no legal route is reason to delay any decision until our state can analyze a route using a process that follows our state constitution," said Jane Kleeb, director of Bold Nebraska, a state-based group that has opposed the pipeline. "This delay is yet more proof this project is not permit-able and not in our national interest."

Several pro-Keystone Democratic senators blasted the delay in statements on Friday. "Todays decision by the Administration amounts to nothing short of an indefinite delay of the Keystone Pipeline," said Sen. Mary Landrieu (D-La.), chairwoman of the Energy Committee. "This decision is irresponsible, unnecessary and unacceptable."

The office of Canadian Prime Minister Stephen Harper also criticized the delay. "We are disappointed that politics continue to delay a decision on Keystone XL," Jason MacDonald, Harper's director of communications, said in a statement. "This project will create tens of thousands of jobs on both sides of the border, will enhance the energy security of North America, has strong public support, and the U.S. State Department has, on multiple occasions, acknowledged it will be environmentally sound."

This story has been updated to include details from a State Department call with reporters, a statement from Canadian Prime Minister Stephen Harper and details on the Nebraska district court's decision.