WASHINGTON - In a double blow, the newly empowered Republican-led Congress and the Nebraska Supreme Court on Friday undercut President Barack Obama's opposition to the long Keystone XL oil pipeline.

But the White House, which issued a veto threat earlier in the week, said its "position and posture" remained unchanged, and environmentalists said Obama should kill what would amount to "a global warming disaster."

The House voted 266-153 to approve a bill authorizing construction of the Canada-to-Texas pipeline, with 28 Democrats joining majority Republicans in support. It was one of the first pieces of legislation considered by the new, GOP-controlled Congress, which has made approval of the pipeline a top priority and has long been headed for a confrontation with Obama on the issue.

The Republican cause was emboldened Friday, when Nebraska's highest court tossed out a lawsuit challenging the pipeline's route, an obstacle the White House said must be removed before it could decide whether the huge cross-border project was in the national interest and the administration could proceed with its own review.

"We shouldn't be debating it, we should be building it," said House Majority Leader Kevin McCarthy of California. On the House floor, he read aloud a passage of the administration's veto threat that objected to authorizing the project "despite uncertainty due to ongoing litigation in Nebraska."

Senate Majority Leader Mitch McConnell, following the court's decision, renewed his call for Obama to reconsider his promise to veto the measure.

"Today's ruling provides the perfect opportunity for the president to change his unproductive posture on this jobs project and reverse his veto threat," McConnell said. "The president now has every reason to sign it."

But a White House spokesman said the court's decision changed nothing.

"Regardless of the Nebraska ruling today, the House bill still conflicts with longstanding executive branch procedures regarding the authority of the president and prevents the thorough consideration of complex issues that could bear on U.S. national interests, and if presented to the president, he will veto the bill," said deputy press secretary Eric Schultz.

The House vote marked the 10th time the chamber has voted on legislation to advance the Keystone XL pipeline, an $8 billion project that would carry tar sands oil from Canada to Gulf Coast refineries along a proposed 1,179-mile route through Montana, South Dakota, Nebraska, Kansas and Oklahoma.

Strong as the vote was, it fell short of the two-thirds majority that would be needed to override a presidential veto. And the Senate, though newly controlled by the Republicans, is also likely to fall short of that threshold. The Senate is expected to clear a test vote on an identical bill on Monday.

The proposed pipeline is at the center of a major political fight. Environmental groups have waged protests, including arrests, in an effort to halt what they view as an environmentally destructive project that would unravel the progress the administration has made to combat climate change. They called on the White House to reject TransCanada Corp.'s permit request outright on Friday after the Nebraska court decision didn't go their way.

The Nebraska Supreme Court let stand a 2012 state law that allows the governor to empower Calgary-based TransCanada to force eastern Nebraska landowners to sell their property for the project.

If the decision had gone the other way, the State Department, which is in charge of evaluating the pipeline's environmental risks, may have had to do additional analysis. A State Department spokeswoman said Friday it would now move forward with its review by seeking comment from eight federal agencies about whether the pipeline is in the national interest.

"No matter the route, as long as the pipeline is carrying tar sands oil it is a global warming disaster and fails the president's climate test," said May Boeve, executive director of 350.org, an advocacy group that has orchestrated many of the protests against the project. "It's time for President Obama to build on his veto threat and reject Keystone XL outright."

Republicans argued on Friday that the pipeline was a jobs creator and critical infrastructure that could further wean the U.S. off Middle East oil. Pointing to a State Department review that found the pipeline would not exacerbate global warming because the oil would otherwise be transported by other means, they said it was a safer and more environmentally sound way to transport oil.

"The president has been hiding behind the Nebraska court case to block this critical jobs project," said Rep. Fred Upton of Michigan, the top Republican on the House Energy and Commerce Committee. "With that contrived roadblock cleared, the White House is now out of excuses and out of time."

Democrats, meanwhile, kept up their criticism of the project.

Rep. Frank Pallone, D-N.J., the top Democrat on the Energy committee, said building the pipeline would increase reliance on Canadian tar sands oil and reverse the strides Obama has made to reduce pollution blamed for global warming.

"We get all the risk," he said, "while the oil companies will reap all the rewards."