(I'm) (a)fraid not
A response used to reluctantly decline an invitation or politely answer a question in the negative, indicating regret that the answer is "no." When the phrase is abbreviated to "fraid not," an apostrophe is often used in place of the missing letter. A: "Will you be able to attend the meeting tomorrow?" B: "I'm afraid not. I'm going to be out of town." A: "Could you loan me a hundred bucks?" B: "’Fraid not. I'm broke."
See also: not
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
(I'm) afraid not.and 'Fraid not.
I believe, regrettably, that the answer is no. (The apostrophe is not always shown.) Rachel: Can I expect any help with this problem? Henry: I'm afraid not. Andrew: Will you be there when I get there? Bill: Afraid not.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.