I want to know the answer to the following question:
Who proposed that change was needed in the way business with the Greeks was to be conducted  ?
All the background I'm provided with is that "In later times, the Romioi plied the sea-lanes of the Mediterranean and controlled trade until an embargo imposed by the Roman Emperor on trade with the Caliphate opened the door for the later Italian pre-eminence in trade.". Is that enough to answer the question?
Answer: yes