Didier Deschamps’ men had struggled in the opening exchanges as if groggy from the frenzied atmosphere generated by the home fans prior to kickoff.
Stancu should have put Romania ahead after three minutes, his side-foot effort from inside the six-yard box blocked by France keeper Hugo Lloris.
“Had we scored that would have changed the whole match,” said Iordanescu, who is in his third stint as Romania coach having guided them through the qualifiers unbeaten with the competition’s best defensive record.
“I would like to congratulate my players for having implemented all of the tactical instructions I give them.
“I thank them for the quality of their play as well as having provided a good result despite the fact we ultimately lost the game,” he added.
Romania, seeking a first win at the European Championship finals since 2000, play Switzerland on Wednesday before their final group game against Albania on June 19.