If this question arises early, odds are that the interviewer is really asking: “Can we afford you?” If it arises much later, the interviewer may be hoping that your salary requirements are aligned to what they have budgeted for their role.
Start off by giving a salary range instead of a specific number. Then demonstrate neutral research, which establishes you as trustworthy, bold and grounded. Also substantiate why you should be at that higher range, which comes across as confident and steady.
I've been doing some research on the market for the role of Business Analyst. What I found from the LinkedIn's salary tool and Glassdoor, is that here in London, base pay for these jobs tends to run between £55,000 and £65,000. Half the companies pay bonuses as well. Given the global impact of your company, and the fact that candidates with Master's degrees, like me, are being recruited most heavily, I think we should be looking toward the top end of that range.
Other Interview Tips:
Always match your strengths with the job description
Show why your a great fit
Share a success story using the STAR framework
If you feel overwhelmed by the thought of your next interview, Bigger Fish offers interview coaching to help you overcome anxiety and teach you how to answer difficult interview questions.