Sen. Rand Paul (R-KY), a member of the Senate Foreign Relations Committee, will oppose Elliott Abrams if President Donald Trump nominates him to serve as the Deputy Secretary of State, a senior aide to Paul confirmed to Breitbart News late Monday night.

Paul’s decision to come out against Abrams strikes a damaging blow against his chances of ever receiving Senate confirmation should he be nominated, outside of bipartisan support that he’s unlikely to receive or a full-court press by Senate Foreign Relations Committee chairman Sen. Bob Corker (R-TN) and Senate Majority Leader Mitch McConnell.

With 21 members—11 Republicans and 10 Democrats—if the Democrats on the Senate Foreign Relations Committee hold strong against Abrams should Trump select him, Paul’s vote would be the deciding vote and he would fail in Committee. His decision to oppose Abrams per a senior aide puts the kibosh on Abrams’ chances once and for all, unless a Democrat on the Foreign Relations Committee comes out for him–or unless McConnell and Corker try to bring him up straight on the Senate floor despite failing in Committee, something a senior Senate aide tells Breitbart News is not usually done.

Given how difficult Paul’s decision here would make it to get Abrams through the Senate to confirmation should he be nominated, it’s unclear if Trump and his White House would want to go to such lengths to fight for someone who disagrees with the president on so many core policy visions. Abrams does not believe in an “America First” foreign policy vision, is from a wing of the GOP that Trump regularly criticizes, and has significant disagreements with Trump’s stated vision on core matters like the Middle East and the Arab Spring.

Paul’s efforts, a senior aide adds, are meant to be constructive. Since Abrams’ policy viewpoints don’t match Trump’s vision for foreign policy, Paul believes that Trump should turn to someone else. Paul will make this argument, and officially make his announcement against Abrams, in an op-ed that will be published on Tuesday.

“In a country of 300 million people, surely there are reasonable foreign policy experts who have not been convicted of deceiving Congress and actually share the President’s foreign policy views,” Paul writes in an excerpt of the op-ed that will run in Rare, obtained by Breitbart News ahead of its release.

The fact Abrams is even being considered for the slot is baffling to many Trump supporters, given that he was aiding the “Never Trump” movement inside the Republican Party—and that he has a foreign policy worldview much more in line with the political dynasties Trump crushed on his way to the White House, the Bushes and the Clintons.

“Elliott Abrams, a neoconservative who has long argued for an activist foreign policy that spreads American values around the world, was advising Republicans just last spring to ‘keep your distance’ from Donald J. Trump and offering advice about what the party should do after the ‘Trump collapse,’” the New York Times’ Gardiner Harris and David E. Sanger wrote on Monday night.

Nonetheless, Abrams has a meeting scheduled on Tuesday at the White House with President Trump to interview for the number two position in the State Department.

The Times reports that Abrams is known in foreign policy circles as “controversial,” but his conviction over misleading Congress in connection with the Iran-Contra scandal from the Ronald Reagan administration “deeply understates the case.” Abrams was later pardoned by Reagan’s successor in the White House.

“He is remembered best for the days when he was an assistant secretary of state during the Reagan administration, and his conviction in 1991 on two misdemeanor counts of withholding information from Congress during the Iran-contra affair,” Harris and Sanger wrote. “He was later pardoned by President George Bush, and that moment has largely receded from memory — although if he is nominated, there is little question that Democrats will bring it up again.”

Before the Republican National Convention in Cleveland in July, the National Interest’s Daniel DePetris noted in a recent piece, Abrams pushed for Republicans to challenge Trump head on at the convention where he would be chosen as the GOP nominee for president.

“Do not allow the Republican convention to be a coronation wherein Trump and Trumpism are unchallenged,” Abrams said, urging the Never Trump movement to challenge him on the floor of the convention. “There’s no reason others who won many delegates, from Rubio to Cruz to Kasich, should not have their names put in nomination. The party needs to be reminded that there are deep divisions, and Trump needs to be reminded of how many in the party oppose and even fear his nomination.”

Abrams also called for Republicans to “seize the party machinery back” from conservatives and grassroots Trump supporters “immediately after the Trump defeat” by Hillary Rodham Clinton, something the man President Trump is now considering for the second highest diplomatic post in his administration said was inevitable, but which turned out not to happen.

P.J. Media’s David Goldman writes that selecting Abrams would be like picking an “arsonist” to serve as a town’s “fire chief.” While Goldman understands that Secretary of State Rex Tillerson may need an experienced diplomat to help run the State Department and “has few good choices,” picking Abrams would be a mistake.

“Bringing the Bush Utopians back into the picture, though, would be a cure far worse than the disease,” Goldman wrote. “During the campaign, Abrams made clear that he would rather see his party fail than see Donald Trump succeed. Inside the administration, Abrams would have the opportunity to make this happen. Arsonists may have great experience with fires, but that doesn’t qualify them to become the captain of the fire brigade.”

Now, with Rand Paul coming out against Abrams preemptively—before Abrams even meets with the president on Tuesday—he may be saving the movement the trouble of a fight.