A bipartisan group of more than half the 100-member U.S. Senate has urged President Barack Obama to approve the Keystone XL pipeline project, which would connect Canadian oil sands to refineries in Texas.
The letter, signed by 53 senators, came a day after Nebraska's governor approved a revised route for the pipeline to travel through the state while avoiding ecologically sensitive areas.
"Nebraska has now addressed the outstanding concerns you raised when you denied the permit, and we therefore urge to finish expeditiously the review process and approve the pipeline" that TransCanada Corp hopes to build, the senators wrote to Obama.
The effort was lead by Senators John Hoeven, a Republican from North Dakota, and Max Baucus, a Montana Democrat, who announced the dispatch of the letter.
The pair organized a similar bipartisan effort in November that drew signatures from 18 senators, nine Republicans and nine Democrats.
Nine Democrats also signed the latest letter, but this time were joined by 44 Republicans.
The U.S. State Department said on Tuesday that it has delayed a decision on whether to approve the pipeline beyond the first quarter of this year. Previously, State had said it would make a decision by that time.
Interest in the fate of the $5.3 billion pipeline has been heightened after Obama's vow at the start of his second term to fight climate change.
"We ask you not to move the goal posts, as opponents of this project have pressed you to do," the senators' letter said.