In Quenyan, no less! You can listen to it here.
Sorry about that, folks, I couldn't resist. Ian McKellen and Christopher Lee were not really impersonating BXVI and Bartholomew, it just sounds like they are. Actually, it's the real thing: the real Pope and the real Patriarch, reciting the Niceno-Constantinopolitan Creed in Greek, not Quenyan, and it is a marvelous thing to hear. Using the original text avoids that whole Filioque thingy.
Thanks to Fr. Kimel for the link.