Rubio fired back. "I don't know how he knows what I said on Univision because he doesn't speak Spanish," he said to his fellow Cuban-American opponent.

Cruz had attacked Rubio for saying different things to Univision than he does in English-language news on immigration.

Saturday night's Republican debate, the most contentious GOP debate of the year so far, got even more heated when Marco Rubio accused Ted Cruz of not speaking Spanish, with Cruz taking to Español to settle it.

"Marco, if you want, say it right now, say it now, in Spanish," Cruz stammered in Spanish.

Cruz was arguing that Rubio goes on Spanish-language television and says different things on the issue of immigration, where past support for the 2013 bipartisan Senate bill has haunted him in the Republican primary.

"Marco went on Univision, in Spanish, and said he would not rescind President Obama's illegal executive amnesty on his first day in office," Cruz said.

However, Rubio has actually been rather consistent on the issue of Obama's executive actions, known as DACA. Around the time he announced his bid for president he told Jorge Ramos, Univision's influential anchor, that DACA "can’t be cancelled from one moment to the next because there already people benefitting.” But Rubio also said, "Yes it needs to end, it can’t be the permanent policy of the United States.”

Asked about it again in November, this time in English, Rubio said, "It will have to end at some point," and later, "DACA is going to end.”



Back at the debate, with no one having understood Cruz anyway, Rubio drove home the second portion of his attack.

"This is a disturbing pattern now," Rubio said. "For a number of weeks Ted Cruz has just been telling lies. He lied about Ben Carson in Iowa, he lies about Planned Parenthood, he lies about marriage, he's lying about all sorts of things."

The two senators have engaged in similar versions of immigration exchanges in a few debates. Cruz always frames it as a battlefield over amnesty, with Rubio, Chuck Schumer, and Obama on one side, and Cruz, Jeff Sessions and Steve King on the other, along with the American people, of course.

Rubio usually reminds viewers that Cruz wanted to expand H1-B visas 500% and said in an exchange immortalized on video that he didn't want immigration reform to fail.