The French centre-back has been at Lazio since 2006 but is out of contract in the summer and considering his options.
The 25-year-old's agent Ulisse Savini claims Liverpool is the most likely destination for his client but admits there is no rush to do a deal.
"Liverpool is our first option for June," Savini told tuttomercatoweb.com.
"It's in issue in progress and we have to talk yet.
"Everyone knows that the contract is expiring. Also, Lazio know there is no hurry.
"We'll see in the coming days. However, it would be hard to say no to Liverpool."
The Reds have options at the back but are believed to be looking for defensive additions in the summer with vice-captain Jamie Carragher yet to agree a new deal at Anfield.