ROUGH CUT (NO REPORTER NARRATION)<br/> <br />The Republican-led U.S. House of Representatives passed a bill on Friday that would approve construction of the Keystone XL pipeline, but prospects for the Senate approving the measure were uncertain.<br/> <br />TransCanada Corp's controversial $8 billion pipeline would help transport crude oil from Canada to the Gulf of Mexico, but is opposed by environmentalists.<br/> <br />An identical bill will be considered by the Senate next week but may lack the votes to pass. The bills also could face a veto threat by President Barack Obama.
