You will need an RT license to be able to talk on the radio.
Whereas I believe that in theory you may be able to obtain a PPL without an RT license, it would severely limit the places you could fly from, to and over, rendering your license as good as useless.
There is an exam dedicated to radiotelephony which is mandatory for the issuance of a PPL. There is then a separate practical test which you need to pass to obtain the RT license itself.
HTH,
B.
Last edited by Baikonour; 1st Sep 2016 at 22:39.
Reason: typo