Deferring a place and reapplying to Oxford

Hi just a quick question that I have been trying to find an answer to!

This year I applied to read Philosophy and Economics at several places including UCL, and I got an offer from UCL (My first choice this admission cycle). I wanted to know if it was possible to defer a place for next year at UCL and then apply to Oxford (my dream uni) for History and Economics, so that if I didn't get in the second time I could just take up a guaranteed place at UCL?

I haven't been able to find an answer to this. I just wanted to know if it was possible or not, or whether I would have to give up my deferred place at UCL to re-apply anywhere else.