Arsenal defeated Liverpool 1-0 at Anfield on Sunday in the ninth round of the Premier League, with Kai Havertz scoring the only goal.
The win took Arsenal to 24 points and outright first place. Manchester City stayed on 21 points after losing to Brighton on Saturday.
The result also ended a 14-year wait for Arsenal at Anfield. Since 2012, Liverpool had won eight and drawn five of the meetings there.
Liverpool dropped from fourth to fifth on 15 points, with Chelsea moving to 16 after beating Manchester United.
Both clubs now turn to the Champions League. Liverpool travel to Fenerbahce on Wednesday at 14:45 Brasilia time, while Arsenal visit Slavia Prague on the same day at 17:00.
Sources: CNN Brasil.