Washington (CNN) President Barack Obama will veto the Keystone XL bill if Congress passes a measure green-lighting the oil pipeline, White House press secretary Josh Earnest announced on Tuesday.

The pipeline is currently in a final phase of review from the State Department, which has already concluded that it would have a minimal impact on the environment. But the State Department also assessed that the pipeline would create about 42,000 jobs directly and indirectly during the construction period -- but just 50 permanent jobs.

The White House reviewed the text of the bill to authorize the pipeline on Monday, Earnest said.

Obama's objection to the legislation, Earnest said, is not based on the merits of the project so much as the idea Congress was trying to take the decision out of the hands of the executive branch.

"The President has been pretty clear that he does not think that circumventing a well-established process for evaluating these projects is the right thing for Congress to do," Earnest said.

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