Former Republican presidential nominee Mitt Romney accused Ted Cruz on Thursday of going “way over the line” in his criticism of President Obama and the nuclear deal with Iran.

“I am opposed to the Iran deal, but @SenTedCruz is way over the line on the Obama terrorism charge,” Romney wrote on Twitter. “Hurts the cause.”

Earlier this week, Cruz, the Texas Republican running for president, said: “If this deal is consummated, it will make the Obama administration the world’s leading financier of radical Islamic terrorism.”

Cruz has argued before that Republicans mistakenly nominated John McCain in 2008 and Romney in 2012, two people who he considered insufficiently conservative.

“If we nominate a candidate in that mold,” Cruz warned earlier this year, “the same people who stayed home in 2008 and 2012 will stay home in 2016 and the Democrats will win again.”

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