Mourinho, Chelsea wait with Rooney
Chelsea have seen two offers for Rooney rebuffed by United, who insist the England striker is not for sale.
Mourinho will test that resolve, but not until after the trip to Old Trafford.
"I don't want Chelsea to do it before we go there," said Mourinho, following Chelsea's 2-1 defeat of Aston Villa on Wednesday night.
"Everybody in the club, in the board, they agree with me. They share that opinion.
"I think this period, by the ethical point of view, is a period where we're going to be quiet."
The transfer window closes on September 2, so Mourinho and Chelsea may bide their time over Rooney.
Mourinho has expressed sympathy with the view of managers who believe the transfer window should close before the start of the Premier League season.
Yet the self-styled Special One is still determined to do his utmost to recruit Rooney, who appears unhappy at United.
Mourinho has expressed satisfaction with his squad, which contains three strikers in Fernando Torres, Romelu Lukaku and Demba Ba.
Ba started against Villa, with Lukaku coming off the bench and Torres not in the matchday squad.
There are alternative targets should a third bid fail, with Anzhi Makhachkala striker Samuel Eto'o, who played under Mourinho at Inter Milan, reportedly one of them.
Speaking prior to the Villa clash, Mourinho said: "We have plans B and C. Don't ask me names because it's difficult to speak about players from other clubs."