WASHINGTON (AP) — President Barack Obama rejected an application to build the Keystone XL pipeline Friday after 7 years of federal review, declaring the proposed project wouldn't serve U.S. national interests and would have undercut America's global leadership on climate change.

The 1,179-mile proposed pipeline wouldn't have lowered U.S. gas prices, Obama said, nor would it have contributed to U.S. jobs long-term or make the U.S. less dependent on foreign energy.

Flanked by Vice President Joe Biden and Secretary of State John Kerry, Obama also said the proposed project had taken on an "overinflated role" in U.S. political discourse and had been used as a "campaign cudgel" by supporters and opponents alike.

Killing the pipeline allows Obama to claim aggressive action on the environment. Yet it also puts the president in a direct confrontation with Republicans and energy advocates that will almost surely spill over into the 2016 presidential election.

"This pipeline would neither be a silver bullet for the economy, as was promised by some, nor the express lane to climate disaster proclaimed by others," Obama said at the White House.

Obama also noted that he would travel to Paris in a few weeks to meet with world leaders at an international climate summit. The leaders are expected to finalize a major global climate pact that Obama hopes will be a crowning jewel for his environmental legacy.

Although the project is dead for now, Obama's rejection will likely not be the last word for Keystone XL.

The pipeline's backers are expected to challenge his decision in court, and the Republican-controlled Congress may try to override the president, although those efforts have previously failed. The project could also get a fresh look in 2017 if a Republican wins the White House and invites TransCanada to reapply.

Another open question is whether TransCanada will try to recoup the more than $2 billion it says it has already spent on the project's development. Earlier in the year, the company left the door open to suing the U.S. government under NAFTA.

"This is a day of celebration," said Bill McKibben of the environmental group 350.org. One of the pipeline's most vocal opponents, McKibben said the decision gives Obama "new stature as an environmental leader."

Energy groups immediately blasted the decision, arguing that Obama was discounting years of analysis by federal agencies that they said proved Keystone could be built to be safe and environmentally sound.