Sen. Jeff Flake (R-AZ) split the Senate’s “Gang of Eight” on Tuesday, according to the Huffington Post, discrediting an argument from his fellow Gang of Eight member Sen. Marco Rubio (R-FL) that Rubio used to argue Congress needed to pass immigration reform soon.

“I think that would be very difficult to do,” Flake said when asked if he was concerned that President Barack Obama would sidestep Congress to grant all illegal aliens amnesty like he has done for those under the DREAM Act.

“I don’t think that could happen,” Flake added during the Tuesday event hosted by the Arizona Republic, KPNX-TV 12 News, and USA Today. “I know there is some concern that the president has made it beyond his constitutional mandate on certain issues like that, but I can’t see that happening.”

Flake appeared at the event with fellow Gang of Eight member Sen. John McCain (R-AZ).

Flake’s statement directly contradicts an argument Rubio has made since 14 Republicans joined all of the Democrat members of the Senate to pass the Gang of Eight bill.

“I believe that this president tempted, will be tempted, if nothing happens in Congress, to issue an executive order as he did for the Dream Act kids a year ago, where he basically legalizes 11 million people by the sign of a pen,” Rubio said in mid-August on a Florida radio program.

In her farewell speech on Tuesday, outgoing Department of Homeland Security Secretary Janet Napolitano defended her actions, and those of the administration, in the executive amnesty program known as DACA (Deferred Action for Childhood Arrivals) program. In those remarks, she called for Congress to pass immigration reform in her memory–a seeming admission that President Obama cannot stretch the executive power that far either.

Flake spokeswoman Genevieve Rozansky told Breitbart News that “Senator Flake’s statement speaks for itself.” Breitbart News has reached out to Rubio spokesman Alex Conant for comment.