The Keystone XL oil pipeline may not be a done deal, according to TransCanada, the company that obtained a permit from the Trump administration to build the much-politicized cross-border energy project.

A senior executive told investors Friday that the company is still weighing the economics behind the project and whether oil companies are still interested in using the pipeline that runs from Canada to refiners on the Gulf Coast. It also is awaiting regulatory approvals, which means it won't be able to make a decision on the project until the end of the year.

"Our assessment of these factors will really drive our investment decision when we get into that November-December time frame," said Paul Miller, executive vice president for the company's pipeline division.

President Trump continues to refer to his approval of the Keystone XL permit as a key part of his administration's agenda and in keeping his campaign promises. The Obama administration delayed the project's approval for seven years before former President Barack Obama denied it a permit in November 2015 ahead of the United Nations climate change meeting in Paris.

Keystone XL has "good support" from existing customers, but the company wants new entrants to bolster the commitment to the line before construction begins, Miller said. The company began its open season process Thursday to attract new customers, or shippers, to expand the pipeline's customer base.

Meanwhile, the Public Service Commission of Nebraska is holding a hearing next month over whether or not to allow TransCanada to build the southern leg of the pipeline. Protesters and major environmental groups have formed a project called Solar XL to construct solar panels along part of the pipeline's path through the United States.