Reuters has quoted an unnamed Iranian official as saying that the planes which will be purchased from Boeing will be almost equally split between 737 and 777 models, presstv.ir. reported.
In addition, Iran's national airline Iran Air plans to acquire the latest version of Boeing's 747 jumbo jets.
Half of the 109 aircraft ordered would be narrow-body 737 jets, Reuters has quoted the unnamed Iranian official as saying.
Also, the agreement has yet to be approved by both the Iranian and US governments and the related financing yet to be finalized, it added.
The provisional agreement is the first deal for Boeing with the Islamic Republic since the Iranian Revolution in 1979 and is already seen as the biggest trade agreement in many years between the two sides.
Iran’s Foreign Minister Mohammad Javad Zarif has expressed hope that the agreement would speed up finalizing a $27 billion contract with Airbus to buy 118 planes.
The agreement will only go ahead after receiving export licenses from the US Treasury for the significant American technology built into both Boeing and Airbus airliners.
“We thought to speed up our ties with Airbus, we should make a deal with Boeing first. Now we feel the situation is ripe for both,” Zarif has been quoted as saying.
Iran's air fleet needs a significant upgrade with 230 of its 250 passenger planes requiring extensive maintenance, Reuters has further quoted the head of Iran’s Civil Aviation Organization, Ali Abedzadeh, as saying.