A committee from the Republican-led House of Representatives said it issued a subpoena to the State Department on the permit process for Keystone XL.

The House Oversight and Government Reform Committee said it wanted "all reports, recommendations, letters, and comments received by the State Department" about the Keystone XL oil pipeline planned to cross the U.S.-Canadian border.

The Republican-led Congress that took its seat in January said passing legislation to approve construction of Keystone XL, offered for U.S. federal consideration more than six years ago, was job No. 1. The pipeline has become a scapegoat for U.S. energy policies, with backers touting its energy and economic benefits, while detractors say it's too environmentally risky to support.

The House committee said it's twice asked for documents related what it said was an uncooperative State Department.

"In light of this, a subpoena is necessary and appropriate," said committee Chairman Jason Chaffetz, R-Calif., in a statement. "We will not be stymied in carrying out our responsibility to the American people to effectively oversee the Executive Branch."

Nearly all of the Canadian oil designated for exports heads to the U.S. market. For the United States, Canadian oil represents 33 percent of all imported oil.

In June, Cynthia Quaterman, the former administrator for the federal Pipeline and Hazardous Materials Safety Administration, told delegates at a Houston summit sponsored by energy reporting agency Argus the Keystone XL pipeline might not fit in the U.S. oil landscape because of increased domestic production.

An executive order gives the U.S. State Department vetting power over the pipeline. President Barack Obama earlier this year vetoed legislation the White House said circumvents the normal vetting procedures for the pipeline.