Mourinho: It's out of our hands
Goals from Mohamed Salah, Frank Lampard and Willian moved Mourinho's men to the Premier League summit but the Portuguese knows that Chelsea are still relying on other results to go their way.
Liverpool can regain top spot by beating West Ham on Sunday, and Mourinho still has to take his side to Anfield before the season is over.
"I keep saying that we don't depend only on ourselves and we never did," the Chelsea manager told Sky Sports.
"I was waiting to be top of the league and depending on ourselves but that has never happened. We depend too much on other results.
"We have to play Liverpool so we have three points to discuss with them but with Manchester City we don't play them, so they have it in their hands."
Victory soothed the pain of consecutive defeats for Chelsea, who suffered a shock 1-0 reverse in the league against Crystal Palace last Saturday before going down 3-1 at Paris Saint-Germain in the first leg of their UEFA Champions League last-eight tie.
And Mourinho, whose side welcome PSG on Tuesday, was pleased with the reaction of his under-fire charges at Stamford Bridge on Saturday.
"They played well," he added. "Normally after defeats you don't start very confidently and that's what happened.
"But we finished the first half 1-0 and it could have been two or three because we played well in the last 20-25 minutes of the first half.
"The second goal (arrived) and the game is over, everything was under control.
"It is a good victory and it's what we have to do until the end of the season. We have five matches in the Premier League and we have to win five."