The Foxes find themselves in the bottom half of the Premier League table after registering just eight points from eight games, but so far they have impressed in Europe with wins over both Club Brugge and Porto.
Victory over Copenhagen on Tuesday night would move the Foxes to the brink of qualification for the last 16 of the Champions League, and Ranieri has acknowledged that he is currently prioritising that competition over domestic fixtures.
The Italian is quoted by BBC Sport as saying: "In the Premier League we must be safe at the end of the year. The Champions League is now. At this moment, it's a priority."