Kursad, I doubt this was the reason because:
1) Iranians already had Fulcrums bought directly from russia in 1990
2) Iranians got more Fulcrums from Iraq during Desert Storm
3) As you can understand from 1), Russians did not and have not problem selling Iran military aircraft directly
4) The Fulcrums were rather disappointment for IRIAF, so Iranians were not interested in further purchase
Jan,
This reason was very well publicized and generated a lot of discussion in publications all over the world; it is not my own speculation. The Moldovan Mig-29's were said to be nuclear capable, and