Sen. Dick Lugar (R-Ind.), the top Republican on the committee and a key backer of the pipeline, called for immediate approval of the project during a hearing on the State Department's proposed fiscal 2013 budget.
“Given the intensity of multiple crises in the Middle East and the certainty that threats to oil supplies are not limited to the current crisis with Iran, it is incomprehensible that the President has rejected approval of the Keystone XL Pipeline,” Lugar said.
"Few national security decisions of the past several decades are more clearly at odds with core U.S. interests than the President’s pipeline delay,” he said.
TransCanada initially applied for permission to build the pipeline in 2008, and said Monday that the new application would come in the “near future.”
“At this point I obviously cannot make any comment on a hypothetical application and permit, but I do think your concerns and the concerns of others about the pipeline, both pro and con, suggests that it's important that the process follow the laws and regulations, because whatever the outcome it is likely to be controversial, whichever way the decision is finally made,” Clinton told Lugar.
Separately, in a process that's not overseen by State, TransCanada announced Monday that it plans to proceed with a portion of the pipeline to bring U.S. crude from Cushing, Okla., to the Gulf Coast.
The White House pledged support for that portion, but hasn’t tipped its hand on the broader proposal to bring oil sands from Canada to Texas.
Environmentalists oppose Keystone XL due to greenhouse gas emissions from extracting and burning Alberta’s oil sands, fears of spills along the route and other factors, while industry groups and other backers call the project a way to boost energy security and create jobs.
President Obama, when the administration rejected the cross-border permit in February, said the decision was not on the merits but instead because Republicans set an “arbitrary” deadline in payroll tax cut legislation.