The two clubs have long shared a bitter rivalry and this has only intensified since Reds striker Luis Suarez was banned for eight matches for racially abusing United defender Patrice Evra at Anfield in October.
Suarez has two matches of his ban left to serve, but it is expected that Evra will play.
Dalglish said: "We want to concentrate on going out and playing football and any other sideshow is purely that, it is just a sideshow."
United boss Alex Ferguson added: "We want to make sure we are talking about the game, nothing else."
The Scot refused to say whether he would pick Evra, saying: "I am not getting involved in that."