Teenager Januzaj enjoyed a breakthrough campaign at Old Trafford in 2013-14, making 27 Premier League appearances under David Moyes.
However, the Belgian forward's first-team opportunities have been much more limited so far this season, with Van Gaal starting him just four times in the top flight.
The arrival of Angel Di Maria in August and emergence of young striker James Wilson have seemingly pushed Januzaj further down Van Gaal's attacking pecking order, leading to reports that he could leave Old Trafford on loan in order to play more first-team football.
The likes of Paris Saint-Germain and Everton are said to be interested in offering Januzaj an escape route, but United boss Van Gaal has moved to quash any talk that the 19-year-old is on his way out.
When asked if Januzaj needs the experience of playing elsewhere on loan, Van Gaal told United's official Twitter account: "No. He is a player of United."
Januzaj was an unused substitute in United's 1-1 draw at Aston Villa last Saturday, but will hope to play some part when Newcastle United visit Old Trafford on Boxing Day.
