The Red Devils left back says last year's Premier League runner-up is eying this season's title rather than being concerned with the performances of its rival.
Roberto Mancini's side currently sits seven points behind United - one less than the margin City hunted down at the end of last season to win its first league title since the 1967-68 campaign.
"This year we are focusing more on ourselves, whereas last year we were more worried about City," he told Canal+. "There was too much focus on what they were going to do in their next game. But this year it's about us. By having a good season, we will become the champions.
"We finished last season with the same number of points as the champions and it was obvious we are stronger than last year given the addition of players like [Robin] Van Persie and Shinji Kagawa."
United has been in fine form in the Premier League this season, winning 18 out of a possible 22 matches and going unbeaten in 10 games since a 1-0 defeat to Norwich on Nov. 17.