The U.S. Senate was scheduled to vote Wednesday on 18 amendments related to the Republican-led bill to approve the controversial Keystone XL pipeline, more amendments than they debated in all of 2014, according to a spokesman for Senate Majority Leader Mitch McConnell’s office. President Barack Obama has indicated he would veto the Keystone project if it passes Congress as expected.

The votes on the Keystone amendments were scheduled for 2:30 p.m. EST Wednesday and included 10 Democratic-sponsored amendments and eight sponsored by Republicans, McConnell spokesman Don Stewart said in an email. The debate on the amendments comes two days after Democrats quashed McConnell’s plan to hold a vote on the Keystone bill. A measure that would have set the legislation up for a final vote was defeated after Republicans fell seven votes short on the procedural vote, according to the New York Times.

Democrats said they were angered at how McConnell is running the Senate since he became majority leader earlier this month, accusing him of going back on his promises to have full debates on bills. "Sen. McConnell promised Democrats an open amendment process and a full-throated debate on the Keystone pipeline, and we are holding him to that promise," Sen. Chuck Schumer, D-New York, said in a statement, according to NBC News. "Trying to muzzle the debate by refusing to allow Democrats even one minute to advocate for their amendment and then simply refusing to hold votes on dozens of other amendments is not a remotely 'open' process."

McConnell fired back, arguing Democratic Senate leaders were pressuring their members to oppose the pipeline, which would transport crude from western Canada to the United States. "We've heard rumors that some in the Democratic leadership are pressuring rank-and-file Democrats -- even Democrats who co-sponsored this bill -- to block Keystone's jobs with a filibuster instead," he said. "This is really disappointing when you consider all that our friends on the other side have been saying about the filibuster for so many years."

Obama threatened to veto the legislation on grounds that it won’t create nearly as many jobs as its proponents suggest, environmental concerns and that the State Department, not Congress or the president, should decide Keystone since its development involves a foreign country.