The 15-year-old, who plays for Brian Deane's Sarpsborg side, linked up with United last week and featured for their Under-18 side in a match at Aston Villa.
"The experience has been fantastic," Haug is quoted by Sarpsborg Arbeiderblad.
"Here they care about real people to thrive, and everything is organised in the best way."
Haug revealed that he would be travelling elsewhere after his spell with United.
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball