Nigeria striker Ighalo joined United on loan from Shanghai Shenhua until the end of the season on Friday, returning to the Premier League where he spent a previous spell with Watford.
Although United's interest in Ighalo came late, the player insists he had no hesitation in temporarily ending a lucrative spell in China to join a club he has always admired.
He told MUTV: "From 11pm there was paperwork, negotiating and all that, for the loan deal, so we are talking and other teams are calling them, wanting me. But I told my agent that this is what I want. I want to come here.
"He said: 'You’re going to get a pay cut to go to United.' I said: 'I don’t care. Make this deal happen. I want to go to United. I don’t care how much is the pay cut, I know that, make it happen.'"
Ighalo is likely to get the chance to impress at Old Trafford with a lack of attacking options exacerbated by an injury to Marcus Rashford.
He added: "I’m very happy. It’s just like a dream come true for me.
"People that know me, even back in Nigeria, and even when I was playing at Watford, my team-mates knew that I loved Man United, I support them.
"When I played against Man U, that emotion is there, because it is my dream.
"When we were young in Nigeria, we used to watch the Premier League when the likes of Andy Cole and Dwight Yorke played...
"People supported Manchester United a lot so I developed a love because all my siblings are Man Utd fans.
"I never thought this [move] was going to happen but dreams come true. I am very happy to be here and it's going to be a big and good challenge in my career."
With the Premier League's winter break now under way, United's next game does not come until February 17 when Ole Gunnar Solskjaer takes his side to Chelsea.
United is currently seventh in the table, six points adrift of the Blues, who occupy fourth.