WASHINGTON – House Speaker John Boehner warned President Barack Obama that if he acts alone on immigration, Republicans will do whatever it takes to stop him. It is starting to look more and more like the type of showdown that could lead to a government shutdown -- although Mitch McConnell, the next Senate majority leader, has vowed to avoid such a step. So the fight, it's clear, is not between the president and the Republicans only; it's also an inside struggle for control of the GOP.

“We’re going to fight president tooth and nail if he continues down this path,” Boehner said on Thursday. “This is the wrong way to govern. This is exactly what the American people said on Election Day they didn’t want. So all the options are on the table. We’re having discussions with our members and there are no decisions that have been made as to how we will fight this if he proceeds."

He added, “When we have a decision, we’ll let you know.”

It was the most aggressive stance the speaker has taken against Obama since the two began swapping warnings about immigration last week. Boehner wouldn’t rule out shutting down the government to stop Obama’s plan to use executive actions to stop the deportation of undocumented immigrants.

“Our goal is to stop the president from violating his own oath of office and violating the constitution,” Boehner said. “It’s not to shut down the government.”

It was a very different tone than that sounded earlier in the day by Senator McConnell.

“We will not be shutting the government down or threatening to default on the federal debt,” McConnell said when asked about conservative calls to attach immigration-executive-order-blockers to the spending bill.

Boehner’s strong remarks came after he met with his membership for hours to decide the Republicans leaders for the next session of Congress. Boehner will remain speaker, but he has been struggling for years with growing opposition from the most conservative members of his conference, and it's clear that he doesn't feel he can accommodate the president or give up any bargaining chips. 

Right-wingers in Boehner’s conference have been pushing him to use a government spending bill that must be passed by Dec. 11 to stop Obama’s planned action on immigration. If that spending bill isn’t passed and becomes law, the government will shut down. The lead up to the government shutdown in 2013 was similar: House conservatives pushed for a defunding of the health care law to be tied to a must-pass spending bill. Senate Democrats refused to pass it. Obama said he wouldn’t sign it. Result: 16 days of gridlock.

In this case, it would be unlikely Obama would sign legislation that undoes the executive orders he is planning to issue. Boehner wouldn’t say whether he thought any of the efforts being considered by his members could even work.

“We’ll find out,” Boehner said. “If he wants to go off on his own, there are things he’s just not going to get.”