The 28-year-old Irish international and his family want to return to the UK, and after the club said they are willing to let him leave, Stuart Pearce is thought to have been the first Premiership boss to make an enquiry.
The 27-year-old Diawara is a Senegal international who almost joined Portsmouth on loan in January and has also attracted interest from Spurs and Newcastle.
But Sochaux want £5.5m for the central defender and Pompey are also interested in a permanent deal.
"I want to come to England," Diawara said during the African Cup of Nations in January.
"I have decided I want to play in the Premiership and I believe I have the game suited for English football. Any club that signs me will not be let down."