Roy Hodgson's men face Scotland at Wembley on Wednesday in a friendly with the Red Devils star expected to feature despite missing his club's Community Shield victory over Wigan on Sunday.
Goal understands that Rooney remains determined to leave Old Trafford this summer with Chelsea having had two bids for the striker rejected, but Hart is adamant that the striker is purely concentrating on England at the moment.
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"He has got stuff going on in his own life and his own football career but, at the moment, he is here with England and I am pretty sure all he is focused on is Wednesday night."
Hart also hinted that the friendly, which comes just days before the start of the Premier League season, might prove to be a welcome distraction for Rooney, who has rarely been out of the headlines this summer.
"Literally, you are away from your club - nothing to do with your club," he added. "You are representing England, the same as when you are with your club, you are representing your club, so I think it's a welcome environment, it's a safe environment in terms of players and staff and people who are involved with England.
"I can't talk for him, I can only talk for myself, and whenever I have come here all that I have focused on is England."