I cannot accept a compensation lower than...
'Inferiore' = in-feh-RYO-reh. Four syllables; stress the third.
Use this only when you need to set a firm floor in negotiations, after softer approaches have been exhausted. This phrase signals your bottom line and should only be used when you mean it.
The present tense 'non posso' (I cannot) is stronger than 'non potrei' (I could not). It signals a non-negotiable limit. Using this without genuine backing removes your credibility — only state it if you are prepared to walk away.
La mia soglia minima è...
My minimum threshold is...
'Soglia minima' is business language for bottom line
Al di sotto di questa cifra, non sarei in grado di procedere.
Below this figure, I would not be able to proceed.
More formal and indirect; slightly softer than 'non posso accettare'
Ho delle spese fisse che non mi permettono di scendere oltre.
I have fixed expenses that do not allow me to go lower.
Personal framing; less effective in Italian business culture — use data instead
In Italian corporate culture, stating a 'non-negotiable' position can be seen as inflexible. It is more culturally intelligent to leave a door open (as shown in the dialogue) even when holding firm on the number. Pure ultimatums are rarely effective in Italian negotiations.