As President Barack Obama, Senate Majority Leader Harry Reid, House Minority Leader Nancy Pelosi, and the rest of the left-wing network lobbying for House Republicans to pass immigration legislation gear up for a renewed push, leaders of the conservative movement are calling on House Speaker John Boehner to once and for all make the public promises necessary to close the door on amnesty.

In a letter that a coalition of more than 130 local and national conservative leaders have signed, provided exclusively to Breitbart News ahead of its public release, the signers call on Boehner to close down Obama’s pathway to amnesty. They specifically are calling on Boehner to publicly close down any procedural avenues, like a conference committee, that could be used to somehow revive the Senate “Gang of Eight” bill. At this point, Boehner has not made the promises these leaders are calling for.

“We applaud your commitment to applying the Hastert Rule to immigration legislation pending before the House of Representatives,” they wrote. “As you know, the Senate immigration bill, S. 744, would undermine the rule of law by granting amnesty to those here in violation of current law, it would devastate millions of un- and under-employed American workers, and it would cost trillions of dollars in additional entitlement and health care spending.”

Boehner just broke the Hastert Rule, an informal but usually followed unwritten rule that the Speaker must have the support of a majority of his conference before bringing any legislation to the House floor, to pass the fiscal deals that ended the government shutdown and raised the debt ceiling. Boehner has, however, promised that with regard to any immigration bills, he will not break the Hastert Rule.

Unlike the fiscal deals, there is no urgency or deadlines to deal with immigration, so conservatives would rather the House get it right before passing anything. But they argue that a piecemeal approach, as has been advocated by House leaders, will fail if not done correctly. They believe the Senate bill should never be allowed to be combined with any House bill or group of bills via a conference committee, which Gang of Eight members Sens. Chuck Schumer and Bob Menendez, along with Senate Majority Leader Harry Reid, want to do.

“Considering and enacting narrowly focused immigration legislation that targets specific failures of the current system is the correct and responsible approach to addressing this complicated issue,” the coalition of conservatives wrote in their letter to Boehner. “However, this approach will fail if the end result of the deliberative process is a conference or other closed-door negotiations with the Senate immigration bill. Even if the House were to pass a perfect immigration bill, combining it in any way with the Senate bill–through procedural moves or otherwise–would lead to disaster, due to the overwhelming flaws in the Senate bill.”

Specifically, conservatives are asking Boehner to make a public commitment that he will not allow any procedural trickery like what Reid wants to do on immigration. Without such a public commitment, they feel they will have to publicly oppose any immigration legislation because of the fear Boehner may use even good conservative bills like the SAFE Act interior enforcement bill from Rep. Trey Gowdy (R-SC) as a mere bargaining tool to combine with the Senate bill in a conference committee.

“We therefore write to ask you to make a public commitment that the House of Representatives will not conference any House immigration bill with any version of the Senate immigration bill or engage in any informal negotiations to do so,” they wrote. “Only once the dangers of such a conference have been set aside should the House proceed with consideration of any immigration-related legislation. In the absence of such a commitment, we, and the millions of Americans our organizations represent, will have no choice but to oppose all efforts to bring any immigration legislation before the House of Representatives.”

The letter was sent to Boehner on Thursday, and copies were also sent to House Majority Leader Rep. Eric Cantor (R-VA), Majority Whip Rep. Kevin McCarthy (R-CA), GOP conference chair Rep. Cathy McMorris Rodgers (R-WA), and Judiciary Committee chairman Rep. Bob Goodlatte (R-VA). Each of those other members of GOP leadership has also refused, like Boehner, to take a public stand against going to conference with the Senate bill.

Signers of the letter include: NumbersUSA president Roy Beck; Eagle Forum founder and president Phyllis Schlafly; Heritage Action CEO Mike Needham; Tea Party Patriots co-founder Jenny Beth Martin; Center for Security Policy President Frank Gaffney; Progressives for Immigration Reform Executive Director Leah Durant; ProEnglish Executive Director Bob Vandervoort; Federation for American Immigration Reform (FAIR) president Dan Stein; American Values president Gary Bauer; and among more than a hundred local Tea Party activists from all around the country.

These activists are hardly the only people calling on Boehner to be public and open about what his real plans are. Many members of Boehner’s own conference, including, among many others, Reps. Ron DeSantis (R-FL), Pete Olson (R-TX), Matt Salmon (R-TX), and even Raul Labrador (R-ID), who at one point supported immigration reform efforts, have all come out and called for no conference with the Senate bill. Senators like Sens. Rand Paul (R-KY), Jeff Sessions (R-AL) and Mike Lee (R-UT) have called on Boehner to publicly promise against conference as well.