The White House’s carefully-worded veto threat on Tuesday against pending legislation to greenlight construction of the Keystone XL pipeline could leave environmentalists concerned.

When pressed if the White House’s veto is based on an objection to the project itself, Press Secretary Josh Earnest said the President will “withhold broader judgment” on the pipeline, but opposes Congress’ move to inject itself in deliberation.

“The concern that we have right now is principally on the idea that this piece of legislation would undermine what has traditionally been, and is, a well-established administrative process to determine whether or not this project is in the national interest,” he said.

The process Earnest is referring to depends on a Nebraska Supreme Court decision, due any day now, that will yield a finalized route for the pipeline. After the issue is litigated, the State Department’s formal review of the project is expected to be completed.

The State Department released an environmental impact survey in 2013, and found that building the pipeline would have nominal environmental impacts. The report stated that rejection of the pipeline was “unlikely to significantly impact the rate of extraction in the oil sands, or the continued demand for heavy crude oil at refineries in the United States.”

That report later came under criticism after it was revealed that the State Department contracted out the compiling of the study to a firm known as Environmental Resources Management–a member of the powerful fossil fuel lobby called the American Petroleum Institute, which has spent millions on Capitol Hill trying to advance KXL.

Earnest did tell reporters they can “note our skepticism about some of the claims made by the most enthusiastic advocates of the pipeline.” Last month, President Obama attempted to debunk points made by Keystone proponents related to job creation and domestic oil supplies.

But the President has often shied away from debating the issue on environmental grounds, much to the chagrin of those who desperately want an ally in the White House talking tough about protecting the planet.

To many greens, Keystone is a symbolic fight. Speaking to journalist Bill Moyers last year, Bill McKibben, one of the leaders in the anti-Keystone XL movement, said he was discouraged by President Obama’s policy on climate change.

“He’s done some good things, but his record is mixed at best,” he said. McKibben also said that Obama “will be remembered at the moment, as the president who produced more carbon than anybody thought possible, unless he begins to act now with real power.”

But the veto threat on Tuesday doesn’t project decisive action or a stand for the environment. Instead, it’s a deferral to forces that have already spurned greens, and suggests that President Obama himself may be the one to green light Keystone XL in the end.