Originally Posted by uszkanni

Consider Qatar FRA-IKA via DOH. If you don't have miles with them or one of their partners, maybe you can use BA miles to get to DOH and buy a ticket to Tehran. I would check the airlines that fly to Iran and see if there is some intermediate transfer point (DOH, DBX, whatever) that you can get to via whatever airline(s) you have or can get miles on, and then buy a ticket to IKA.

In any case, I'd suggest getting a fully refundable ticket. No reason in particular, just saying.