Iowa.  It was a tense moment noticed across the Internet. Last night as Senator Bernie Sanders went to shake Senator Elizabeth Warren’s hand, she appeared to decline. Few people were aware of the actual exchange between the two of them until now. In post-debate audio CNN has revealed a terse exchange between Warren and Sanders. As Sanders reaches out to shake her hand, instead of responding in kind, she can be clearly heard saying, “I think you called me a liar on national TV.”

This is after the Sanders camp was said to have stated to Warren that a woman could not be President. It was considered to be only an anonymous unknown-sourced piece of information until Warren herself confirmed the statement in a response during the debate. Since then, Sanders and Warren have been in the news caught in a “he said, she said” moment, where the only two people that were definitively in the room were Sanders and Warren themselves.

Tonight, on the debate stage, Sanders denied Warrens charges, claiming that he had supported a woman president since the 1980s and even claimed that he encouraged Warren to run before he joined in, in the 2016 election. Clearly, Senator Warren was deeply upset, not only saying, “I think you called me a liar on national TV.” With Senator Sanders responding that she was in fact calling him a liar as well.

While we many never know for sure who is actually telling the truth, this appears to be something of a rift between political friends. How deep the rift goes remains to be seen.

The full dialogue is below:

Warren: “I think you called me a liar on national TV?”

Sanders: “What?”

Warren: “I think you called me a liar on national TV.”

Sanders: “No — let’s not do it right now. You want to have that discussion, we’ll have that discussion—

Warren: “Anytime.”

Sanders: “You called me a liar, you told me — alright, let’s not do it right now.”