Mourinho was speaking at the start of Chelsea’s Asian tour in Bangkok, just hours after Rooney pulled a hamstring on the first day of United’s visit and abruptly left the Thai capital.
“It’s a funny, tricky question because from the ethical point of view, I cannot speak about players from other teams,” Mourinho told journalists at a plush downtown hotel.
“But again you know me and you know it’s not my kind of character to speak with a little bit of hypocrisy. I always say what I feel, what I think.
“I’ve always said he’s a player that I like very, very much but I cannot say more than that. Being fast and direct, I like him very much but he’s a Man United player.”
Mourinho is seeking a striker to complement the erratic Fernando Torres and he has brought back Romelu Lukaku after a loan spell at West Bromwich Albion following his return to the London club.
Concerns over Rooney’s future were not eased by his sudden departure just hours into the United tour, announced in a two-line statement on the club website, which said he would be out for a month.
However, Rooney said on his Facebook page that it was just a “niggling injury” and “nothing to worry about”.
Rooney has declined to confirm his plans for the future after departing United manager Alex Ferguson said in May that the 27-year-old forward had asked for a transfer.
This week, Britain’s Daily Mail said Chelsea were preparing a 60-million-pound ($90-million) bid for Rooney, who has also been linked with Paris Saint-Germain and Arsenal.