I signed a contract with lawyer. In this contract, some fees were specified to be paid at agreed conditions. Any other fees, beyond the scope of a contract, were to be negotiated and agreed on in a separate agreement.
At some point, lawyer suggested that he could perform some action on my behalf (let's call it "service"). The service was outside of the scope of the agreement. He did not inform me about fees, costs, anything. I agreed. After the service was successfully done, he demanded a substantial fee for the service and he sent me an invoice.
This is of course, the short story. I talked to him about this, but it seems that we've reached a impasse, at which point I received an invoice.
Do I have to pay the fee that I wasn't informed of, and didn't agree on beforehand?
I know this is not really a place to ask this question, but perhaps someone can point me in the right direction. And, if possible, be so kind and use english-english, not law-english, as it is not my native language.