As you know, we use "ی" or "یک" when the object is undefined like 'a' and 'an' in English.
And in Persian we use just one "ی" . You can put it after the first word or second one but just one of them.
For example:
یک کتاب جالب
کتاب جالبی
کتابی جالب
.
یک خانه بزرگ
خانه بزرگی
خانه ای بزرگ
( After "ه" pronunciation of "ی" is hard, so we use "ای" instead of "ی" . It's the same for all vowel sounds to change "ی" some how after them)
There is nothing like خانه یی- ایرانی ییی-بزرگی یی-
.
ایرانی دوستانه
ایرانی دوستانه ای
Here because of this word type that it has 'ye' at the end, you have just one choice: to add ye of undefined after دوستانه