"Dear Senator Ted Cruz, Yesterday, April 28, in your interview with Fox News, you called for my dismissal from Princeton University and made baseless accusations," Mousavian wrote on X.
"I invite you to a public debate so that, while hearing responses to these claims, we can leave the judgment to the American people," he added.
Short of a meeting, Mousavian recommended Cruz read his books, emphasized he supports President Donald Trump's push for an Iranian nuclear deal and said a prison sentence means he cannot return to Iran.
Cruz was unmoved by the invitation and torched Mousavian in a curt reply.
"I try not to be in the room with people linked to Iranian terrorists who have murdered dozens of dissidents."
"Your books are unreadable, and the only debate you should be having is with DHS agents, at the end of which you should be deported," the senator added, referring to the US Department of Homeland Security.
Mousavian was ambassador to Germany when Bonn-based Iranian exile Fereydoun Farrokhzad, an singer and outspoken critic of the Islamic Republic, was murdered in 1992 apparently by agents of the Islamic Republic.
A veteran Iranian commander in March detailed the state's role in his killing, in remarks Mousavian said left him "stunned, amazed, and shocked."
In 2023, several top Republicans, including House Oversight Committee Chairman James Comer of Kentucky and now-DOGE chairman Aaron Bean of Florida, wrote to Princeton with their concerns about Mousavian's tenure.
Several Republican lawmakers wrote an open letter to Princeton in 2023 expressing their concerns over Mousavian's employment.
"A German court found (the Iranian embassy in Germany) served as the headquarters for the planning of the 1992 assassination of four Iranian dissidents," the letter said, referring to the 1994 assassination of four Iranian-Kurdish dissidents in a Berlin restaurant.
"Did Princeton consult with US government officials regarding the hiring of Mousavian?"