Help needed from Italian students!!!

I'm at my final year of high school in Rome and next year I'd like to go to a UK university. The thing is that I've completed all the main points on UCAS, so I've arrived at the point of my reference letter. I have found two teachers who are willing to write it for me, but as I understood they have to put in the letter my predicted grades.
Since here in Italy it's impossible to predict our final grades what can I do? Can my reference only put a predicted grade for the exam (for instance 95) or does he have to put predicted grades for each subject?
Thanks in advanced.

I'm writing on behalf of my son who is in the exact same situation. His chosen referee (english teacher) also chose not to include predicted grades in her reference letter. Now he received 2 conditional offers out of the 5 unis he applied for through UCAS and the conditions are: IELTS score > 6.0 and Grade of Esame di Stato (final year exam) > a certain value. That is fine.
However one of the other Unis has now emailed him asking predicted grades which as you said are impossible to predict and no one in his school seems to want to take responsability for doing. In fact as all italian students of the final year of HS know the final grade of the Esame di Stato needs to take into consideration "Credits" of the last 3 years (3rd, 4th and 5th year of HS), academic merits (Crediti Formativi), bonus points and of course the results of the final exams. So it's impossible to predict and no teacher or school principal will do it as far as I know.

I emailed UCAS on this but we don't really know how best to proceed. The Uni wants a statement on predicted grades from someone in school, not him.

Thanks

This is kind of late, but I would like to know - did your son ever make it into uni? Since this is from last year, I assume he is now already in university or whatever other secondary education path he chose to proceed on. I too am an Italian student and had the same problem regarding UCAS and predicted grades and references a month ago, with my Italian school. Eventually, I resolved to just predict my own grade and take full responsibility for it in front of my school. That really was the only way to have them fill in the predicted grade requirement - another Italian student (or parent) can well understand what I mean. But if someone else had a "happy ending" to this, that would be very reassuring to hear! Thank you.

I am an italian student as well and next year I would really like to apply to a british university. Can i ask you how did you end this situation? What was your school response? And how the did university where you applied reacted? Did the ask you for any type of written certification or past year grades, or just accepted your declaration? Thank you very much it means a lot for me.