Charlton have reported Newcastle to the Premier League after rejecting their offer for goalkeeper Rob Elliot.
The npower League One club turned down a formal bid of £100,000 on Wednesday, but claim Magpies boss Alan Pardew has broken an agreement not to make details of the approach public.
Chief executive Stephen Kavanagh told the club's official website, www.cafc.co.uk: "In advance of our match against Scunthorpe, it is very disappointing that Alan Pardew has decided to make public an offer for Robbie Elliot despite assurances to the contrary that wouldn't happen from his club officials.
"Newcastle made a written offer of £100,000 for Robbie on Wednesday, and made it clear that it was their final and best offer.
"The offer was rejected within minutes, and Newcastle then confirmed they no longer had an interest in the player.
"We have contacted the Premier League today to register our concern at public statements being made by Newcastle after they withdrew their interest."
News of Newcastle's interest in Elliot surfaced late on Wednesday night as Fraser Forster completed his loan move from St James' Park to Celtic.
Asked about the situation at a press conference yesterday afternoon, former Charlton manager Pardew replied: "We have confirmed that Fraser is going to Celtic on loan for the year, and that leaves us with an issue that we need another goalie, really, so we are looking at options to possibly bring one in."
However, when later questioned further by radio reporters, he replied: "Once (a deal for) Fraser was completed, we started looking for another goalie.
"We have enquired about Rob Elliot and we have put a bid in there."