The 19-year-old's displays in Norway's top flight and in the Europa League have brought him to the attention of his national selectors, and he has a great chance of representing Ghana at the African Cup of Nations early next year.
Abu Stromsgodset, who he helped to lift the Norwegian FA Cup the following November. He returned for the start of the next season and so far he has racked up 24 appearances, as well as making his debut for his country.
The new deal with City follows hot on the heels of his first goal in professional football, a 35-yard screamer last weekend against Sogdnal - click here to see it, a minute in to the clip.
A delighted Abu told mcfc.co.uk, "I'm so happy to get a new contract, and to see that the club have a lot of faith in what I've done. I am working towards the day when I can wear a Manchester City shirt in a first team game."