This will be the first derby that Van Gaal has taken charge of since moving to Old Trafford.
Read what else the manager discussed below:
3.47pmGood afternoon! Louis van Gaal is preparing for his first Manchester derby since being appointed manager of Manchester United this summer, and will speak to the media in around 15 minutes' time.
3.50pmUnited should be in a confident mood coming into this match, having come back to share the points with Chelsea last weekend, while the Premier League champions head into the game following a defeat to West Ham in the league and a loss in the Capital One Cup against Newcastle earlier this week.
3.53pmUnlike their hosts, United have had the week off, having not featured in the fourth round of the League Cup earlier this week. They may also have been boosted by the news that their opponents will be without David Silva for this match, as he has a knee injury.
3.56pmUnited have been getting into the Halloween spirit today, naming their spooky starting XI:
4.00pmCaptain Wayne Rooney will be eligible to return this weekend after serving a three-match suspension for getting a red card. Van Gaal should reveal whether Radamel Falcao is ready to return, after missing last weekend through injury.
4.01pmVan Gaal is ready to go, so let's see what he has to say...
4.02pmThe manager starts with an injury update, revealing that Rooney is fit for the derby, but the Falcao will miss out. Antonio Valencia could also feature. On Rooney, Van Gaal adds: "He was never injured, he shall play, he's my captain."
4.04pmThis is the first derby for Van Gaal and he insists that he understands the importance of the match: "This is the biggest derby that I shall manage. It is one of 38 [league] matches we have to play, but for the fans it is unbelievably big as a rivalry and I have felt that also with a lot of the players in the squad, but also especially with Ryan Giggs. When he presented the analysis on City, I felt more tension with him. It was good to see."
4.06pmVan Gaal is asked whether he expects to win this weekend, and he responds: "That is our goal, to win. It is possible, we are growing, we are developing ourselves. What we have seen of City in the last few matches was not so good. You never know."
4.07pmAsked about the importance of Rooney's return, Van Gaal tells reporters: "He has scored a lot of goals against City, the most of any player, so I am very happy that he can play, and he shall."
4.10pmWith Marouane Fellaini playing a greater roll in recent weeks, Van Gaal admits: "He has made a great contribution and also the assist for the goal [against Chelsea]. He has had a lot of time out injured but when he is fit I have played him. He has to continue with that because then I am very pleased."
4.12pmVan Gaal insists that Rooney was not injures, so when asked why the captain was limping last week, he has a rather tongue-in-cheek response: "Maybe his shoes were too tight."
4.14pmVan Gaal reveals that assistant manager Ryan Giggs has been helping him understand the emotion of the derby: "He has transferred the idea of emotion and I have transferred the idea of how we have to play."
4.16pmStill on Giggs, he adds: "He has the experience as a player and now maybe as an assistant manager. We don't have to accelerate this feeling because it is football and you have to play the game, not only a game with emotion but also in a tactical way."
4.18pmDespite the opponents, Van Gaal insists that his job is the same as ever this week: "For me, I have to analyse and prepare for the games in the same manner, it is not different, but for the players and the fans it is different."
4.21pmWell that's all from Van Gaal this week, but join us again on Sunday to find out if United can beat their Manchester rivals. Until then, thanks for joining me this afternoon. Goodbye.