"I think when you're a person like that, when you're famous like that, people are interested, they want to know everything. I don't know what has happened," Ibrahimovic told British media.
"I didn't even ask him because it's not important for me and I'm 100 per cent sure the media doesn't know what really happened. I think we should appreciate him for the player he is, what he did.
"I don't see many players from England who have had the same career as him. I feel a little bit sorry of the situation because we should show more respect for him."
Rooney put in an inspired performance in Thursday's 4-0 Europa League victory over Feyenoord, scoring United's first-half opener from an Ibrahimovic through ball to become the club's all-time leading scorer in Europe with 39.
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The goal also put him just one behind Bobby Charlton's overall club record of 249.
"As a person he's fantastic, I have the luck to get to know the person. As a player, there are no words to not say about him -- he's the perfect player," Ibrahimovic added.
"Everybody knows what he can do, what he did, what he has done. I'm happy for him to break the record and I will help him to go one more -- then I see it as the real record."
United, who are sixth in the Premier League with 19 points from their opening 12 games, host 17th-placed West Ham United on Sunday.
(Reporting by Shravanth Vijayakumar in Bengaluru, editing by Nick Mulvenney)
