Bulgaria coach Stanimir Stoilov says Berba's international retirement has left a huge void.
"For Bulgaria, it is obviously a big loss not to have Berbatov," Stoilov said.
"He will always be missed by the national team and, if he had played, it would probably have been a closer result.
"That was the big difference between the two sides. We missed our chances and they took theirs. But it is Berbatov's decision and we should, of course, respect that.
"I don't want to comment on the chances of him reversing his decision."