Obi, 22, admits he made the move to find regular first team football.
"I'm sorry, but it's obvious," he told FcInterNews. "This is a choice I've made to regain continuity after too many injuries that have held me back.
"I hope to return to Milan as soon as possible.
"Although, from today I will be concentrating on Parma.
"There shouldn't be too many problems acclimatizing to the team - there are a lot of people here that I know."
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