The 18-year-old joined Inter Milan in an £11m deal in the January transfer window, despite reported interest from the Premier League giants. Chelsea, City and United were all linked with the playmaker, but Kovacic insists he would have rejected all three to move to Italy.
The Croatia international could end up costing his Serie 'A' club closer to £13m, with £1.7m to be paid should Inter Milan qualify for the Champions League next season.
And Kovacic is more than happy with his decision, revealing Inter Milan was always going to be his first choice.
"Nobody contacted me directly, but I would have picked Inter either way," Kovacic told reporters.
Kovacic joined Andrea Stramaccioni's side from Dinamo Zagreb two months ago, and he's made three league appearances for his new club so far.
Inter sit sixth in Serie 'A', seven points off third and a qualifying spot for the Champions League. But Kovacic is still hopeful his side will be able to claw back up the table and into a top-three spot.
He continued: "It's hard to get in the Champions League because now we are sixth, but if we play as well as we did against Tottenham we can do it."
Inter beat Spurs 4-1 at the San Siro in the second leg of their Europa League tie, but after a 3-0 first-leg defeat, Stramaccioni's club exited the competition on away goals.
Kovacic said: "We have to play well every game, which honestly we are not doing now. If we all give 120 per cent, we can qualify."