The Black Cats are on the verge of bringing Mensah to the Stadium of Light on a season-long loan deal from Lyon.
Bruce has confirmed talks are still ongoing regarding Mensah and that he is happy with his transfer dealings in bolstering the squad.
"It is still ongoing," Bruce said of the Mensah deal. "He is a Ghanaian international, it's all Home Office, papers and passports all this sort of stuff.
"In principle the two clubs have agreed, the boy wants to come to us and to England so in that respect we are over that hurdle, but we have to make sure we dot the i's and cross the t's and we expect him obviously before the window closes that he can be part of us."
Asked if he would make any more forays into the transfer market, Bruce said: "Well you can never say never.
"I would envisage what we have done is what we are looking at.
"Right down the spine of us now what we have brought in I would be very, very pleased."