Arizona Republican Rep. Matt Salmon said “a lot of dialogue we had today was about setting up a lawsuit,” referring to challenging the Iran deal. (AP Photo/Ross D. Franklin)

House Republicans may have quelled a budding internal revolt with a last-minute tactical switch on the Iran nuclear deal. But now, they have all but committed to settling the Iran fight in the courts — or admitting defeat.

The House plans to vote Friday on a resolution of approval (where a “yes” vote means yes to the deal) instead of a resolution of disapproval (where a “yes” vote means no to the deal) that was previously planned.

House Speaker John Boehner (R-Ohio) promised Thursday that House Republicans will “use every tool at our disposal to stop, slow and delay this agreement from being fully implemented” up to and including suing President Obama to keep him from enforcing the agreement.

“That is an option that is very possible,” Boehner said.

[Senate set to vote on Iran nuclear deal]

The strategy shift comes after a group of House Republicans successfully pressed leaders Wednesday not to play ball with Obama over two confidential side agreements between Iran and the International Atomic Energy Agency (IAEA) that lawmakers have never seen. Without those documents, they argue, Congress’s 60-day review clock under the Iran Nuclear Agreement Review Act never started.

There’s just one problem: In the eyes of the administration, the play clock runs out on Sept. 17. If Congress hasn’t rejected the deal via a disapproval resolution by then, the pact will take effect.

But conservatives pushing this change figure that if Obama isn’t going to hold up his end of the bargain, neither will they. And if the president doesn’t like it? They plan to sue him.

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“The law that the president signed, that all relevant documents have to come to Congress before the clock starts ticking, and those documents never came,” said Rep. Matt Salmon (R-Ariz.) Wednesday.

Rep. Matt Salmon (R-Ariz.) lambasted the international nuclear deal with Iran during a rally at the Capitol Sept. 9. (AP)

“A lot of the dialogue we had today was about setting up a lawsuit,” Salmon said.

On Thursday, House Republicans passed, 245 to 186, a resolution stating that Obama didn’t fulfill his obligations under the law to provide Congress with the text of the side agreements. The resolution also stated that the 60-day clock for Congress to approve the deal hasn’t started.

Meanwhile, their Senate colleagues voted to filibuster a resolution of disapproval, effectively ending the debate in that chamber and preventing the resolution from going to President Obama’s desk for an assured veto. Senate Majority Leader Mitch McConnell (R-Ky.) said he would try one more time before the Sept. 17 deadline, but didn’t seem to hold out much hope of winning.

If Republicans pursue a legal strategy, it wouldn’t be the first time they tried to check an Obama-driven law (see: Obamacare) in the courts. But the tactic wasn’t terribly successful: the Supreme Court sided with the Obama administration on major portions of the health-care law, though lawsuits are still ongoing and Republicans won one legal battle on Wednesday that may embolden them.

The House’s new approach will undoubtedly fail, given that seemingly all Republicans are opposed to the  agreement. But while the exercise allows critics to register their discontent — and claim purity-of-purpose points by not legitimizing the idea that the Obama administration fulfilled its end of the bargain — it won’t do anything to block the deal’s implementation.

The law allowing Congress to review the deal specifically refers to “consideration of a joint resolution of disapproval.” Any other kind of resolution wouldn’t actually prevent the administration, by law, from implementing the deal.

But the Iran Nuclear Agreement Review Act also, critics repeatedly note, refers to “side agreements” as one of the components of “an agreement related to the nuclear program of Iran.”

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Republicans, and a few Democrats, have been pressuring the administration to produce those agreements for weeks, while the Obama administration argues that it can’t because it doesn’t have a copy of the confidential documents. But the law makes no special allowance for such a situation, if Congress wants to press the point.

And this band of House Republicans does — all the way to the courts.

Thus far, the House isn’t moving toward a lawsuit vote. And House GOP leaders still have the right to act on a disapproval resolution.

It’s unclear whether Republicans insisting on a possible lawsuit will acquiesce to the original plan once they have their way.

Meanwhile, across the Capitol, senators are watching their Republican colleagues and shaking their heads.

“Even if the two side agreements were available and pure as the driven snow … I don’t think that would change our view of whether allowing Iran to industrialize their nuclear program is a bad deal,” Sen. Bob Corker (R-Tenn.) said Wednesday.

Corker stressed that he, too, believed the administration had not held up its end of the bargain and that the 60-day clock on Congress’ review period hadn’t started ticking.

But, he added, “the best way to express concerns about the documents, but also concerns about the deal itself, is to vote to disapprove the deal.”

Democrats, confident in their veto-sustaining numbers, are simply standing back and watching the show.

“The question here is quite clear — the Republican conference is trying to make it somewhat confusing: Do you support the agreement or not?” said Rep. Peter Welch (D-Vt.), a member of the Iran deal whip team of House Minority Leader Nancy Pelosi (D-Calif.). “These are tactical conflicts to essentially try to avoid the inevitable. In the Senate and in the House, there is sufficient support to sustain a presidential veto, and they just don’t want that day to come.”

It’s “not so much a decision about a wise tactic as it is a badge of integrity about the purity of their position,” Welch added. “That’s the dilemma over there.”

Correction: Arizona Rep. Matt Salmon’s name was corrected from “Mike” in the original story.