The former Tottenham striker is set to captain the Irish team in the second leg of the Euro2012 play-off against Estonia in Dublin following the 4-0 away win in the first leg.
With the Galaxy preparing for the MLS Cup Final against Houston Dynamo on the weekend, Arena hopes that Keane's duties are lightened so he can be in top form for the decider at The Home Depot Center although he understands the seriousness of his player's job at hand.
"Robbie needs to be there for Ireland," Arena acknowledged. "He's the captain of the team. They've not qualified yet for the European Championship and Robbie will be there.
"I had asked Mr. Trapattoni if he would give it consideration. However in reflecting on that, I really believe that he does belong with the Republic of Ireland for this game in that he's the captain and they haven't made it [yet]. I wanted him to at least consider limiting his minutes if that was possible.
"They need to do what they need to do to qualify. If there's an opportunity for Robbie to get limited minutes, he will. We're hopeful that happens," Arena added.
"Obviously the Republic of Ireland has to make sure they assure their qualification into the championship next year."