I'm afraid not
No, unfortunately · I can't
What's the situation?
This expression is a polite and gentle way to deliver a 'no' or to indicate that something isn't possible, often when you wish it were otherwise. It softens the refusal or negative information. Imagine someone asks if you have an extra pen, and you don't. Or if a project will be finished on time, and it won't. It's like saying 'Sorry, but no.'