The Blues have been given permission to talk to the 27-year-old Senegal international after meeting the £7million figure stipulated in the deal he signed with the Magpies during the summer of 2011.
Ba has been withdrawn from the Newcastle squad for Wednesday night's Barclays Premier League clash with Everton at St James' Park as a result.
The club released the following statement: "Newcastle United can confirm that Chelsea Football Club has made an official offer for Demba Ba which has triggered the release clause in the player's contract.
"The club has given the player permission to speak to Chelsea FC and therefore he will not be included in the squad for Wednesday night's game against Everton."
© Independent Television News Limited 2011. All rights reserved.