O’Neill is keen to land the out-of-favour defender on loan.
The Black Cats chief is already hoping to land Swedish striker John Guidetti from City.
Guidetti is a priority for Sunderland who want extra firepower – with Louis Saha possibly leaving the Stadium of Light if the right offer comes along.
However O’Neill would like to land Lescott, 30, if he becomes available for the rest of the season.
Lescott has lost his place and fears he may need to move on permanently, so a shop window spell would not harm his chances.