Several teams, including the Los Angeles Kings, Detroit Red Wings and Ottawa Senators, are looking to make upgrades on their bluelines, and Regehr is a hot commodity right now.
It's believed the Sabres are looking for a top prospect and a high draft pick in exchange for Regehr.
On Monday, the San Jose Sharks traded defenseman Douglas Murray to the Pittsburgh Penguins for two second-round draft picks.
The Sabres are looking for a similar return, but would prefer a near-NHL ready player included in a package.
The Kings and Sabres have been keeping a very close eye on one another over the last few weeks. Kings GM Dean Lombardi is trying to add a rugged, stay-at-home defenseman to his roster before the deadline passes, and has zeroed in on Regehr.
According to various reports, the Sabres could be discussing an expanded deal with the Kings that also includes winger Drew Stafford, who has sat out the last two games in Buffalo.