President Barack Obama issued the third veto of his presidency on Feb. 24 to reject legislation that would allow the Keystone XL pipeline to be built, Bloomberg reported.

Bloomberg said the veto escalates a battle over the project between the White House and Republicans in Congress.

Notice of the long-expected veto was released without fanfare via a message to the Senate just hours after the bill formally arrived at the White House.

White House press secretary Josh Earnest said it’s “certainly possible” that Obama would eventually approve the pipeline once a State Department review of the project is completed.

“The president will keep an open mind,” Earnest said, without giving a timeline for a decision.