Ronaldo scored twice from the penalty spot to move onto 109 goals for defending champions Portugal as they secured passage to the knockout stages of Euro 2020 with a 2-2 draw against France on Thursday (AEST).
The 36-year-old Ronaldo now needs just one more goal to surpass Daei, who chalked up his remarkable tally for Iran between 1993 and 2006.
Daei was quick to mark the achievement on social media and predict that he will not jointly hold the record for long.
The 52-year-old wrote on Instagram: "Congratulations to @cristiano who is now one goal away from breaking the men’s international goalscoring record.
"I am honoured that this remarkable achievement will belong to Ronaldo - great champion of football and caring humanist who inspires and impacts lives throughout the world.
Ronaldo's first opportunity to claim the outright lead will come when Portugal contest their last-16 tie on Sunday.
Having finished third behind France and Germany in Group F, Fernando Santos' side will take on Group B winner Belgium in Seville.