The Red Devils reached the final of the FA Cup on Saturday by coming from behind to beat Tottenham 2-1 at Wembley, with Lukaku picking up the assist for Ander Herrera’s winner.
But the Belgian striker says that while a cup win would be great, he has bigger prizes in his sights for the future.
“We won against a good side and got to the final. That is great, it is something that we wanted and now we have four games to go in the league where we have to perform really well and then the final,” he told reporters after the match.
“[But] I want to win the title, that is the thing.
“Winning the FA Cup would be nice but I don't want to talk. I just want to end the season well, hopefully take second and that will prepare us really well for the final.”
Lukaku, who joined the club in a £75 million move from Everton last summer, admits it has been United’s inconsistency which has frustrated their hopes of pushing Premier League champions Manchester City closer this season.
“It was a strange season for us,“ added the 24-year-old. “If we had more consistency we could have been up there with Manchester City now. But we know what we have to improve for next season and winning games like this is what we do.
“If you look at games we have played against the top six, we have won a lot of them so when we played against Tottenham we were confident as well. We have to keep going like that.
“I’m really confident in my team-mates. I think we can do it with the team we have now but we should have showed more consistency throughout the season.
“For us now it is up to us to be more consistent and the manager needs to see if he has to add more players, but with the players we have now I think we have enough. We just have to be more consistent.”