As a vocal supporter of the Canada-to-Texas project and a Republican critic of the president, Sen. John Hoeven would be an unlikely candidate to announce the long-awaited decision.
But today, the North Dakota lawmaker told the Senate that's what he's hearing from his sources.
Hoeven says he believes Obama will make the announcement during the August congressional break, in the hope of stifling criticism.
The president has vetoed a Keystone XL bill in the past, but has never definitively slammed the door shut on the project through the normal regulatory process.
Hoeven says rejection makes no sense on environmental grounds, and would disadvantage the oil industry of a friendly U.S. neighbour even as a nuclear deal helps build Iran's industry.
Keystone XL would carry about one-quarter of the oil Canada exports to the U.S. each day, and ease potential bottlenecks on rail lines, but its U.S. opponents argue that it would help develop one of the world's dirtiest sources of oil.
The issue has become a fault line in the U.S. debate over climate change and energy politics. Republicans staunchly support the project, which has divided Democrats.
Asked about Hoeven's remarks, the Conservative government issued a statement defending the project, but said it would refrain from interfering in the American debate.
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