How to ask for increased salary after phone interview

Hi,

I did a phone interview and was asked my salary expectations. I gave the salary from the job I just left. Now I'm thinking I should have asked for around 10% more.

I'm just used to working with recruiters, who might be better at dealing with employers in this regard.

Is it acceptable for me, once I do the face to face interview, to tell them that in fact I'd like to get another few euro on top of what I had previously stated? And if so, how would I even open negotiations on this? Like I said, I usually deal with recruiters who handle all this.

Should I wait until I get an offer/contract and then say "Actually can we discuss salary...?" and see if they'll budge? Or should I get it in early, before I even get an offer? Or should I just accept the mistake and learn the lesson for the future?

Thanks.