Changing chords font size

[Alberto Simões]

Hello

I am entering chords as:

    \chords {
      \italianChords
      s4 fis2.:m e1 fis4:m cis2:m e2 fis\breve:m
    }
    \new Voice = "mel" \melody
    \new Lyrics \lyricsto mel \text

now, I would like to make them smaller (italian chords are verbose).
I am sure there is a parameter for me to override to get that behavior, 
but not sure how/what to change.

Any hint?
Thanks
--
Alberto Simoes
CEHUM