Audley Harrison says that British heavyweight champion Scott Gammer is a "joker" who cheapens the belt.
Harrison has escalated the war of words with Gammer
But Gammer, who turned down a potential February bout with the Olympic champion, says he will be looking for Harrison after facing Danny Williams.
"Gammer has devalued the British title by not fighting the best available challenger," Harrison told his website.
"He spent a year calling me out and as soon as he sees me put in a good fight he runs away from the challenge."
Harrison faces European champion Michael Sprott on 17 February, while Gammer meets Danny Williams - stopped by Harrison in three rounds in December - at the Cwrt Herbert Sport Centre in Neath on 2 March.
When Danny is out of the way Audley is the man I want
"I don't know why Harrison is talking like this, he hardly did anything against Danny Williams," undefeated Gammer, 30, told the South Wales Evening Post.
"Danny didn't fight and anyone can look good when they come up against that.
"But this is typical Harrison. When Danny is out of the way he is the man I want."
Gammer's promoter Paul Boyce added: "After the Danny Williams fight, Audley won't have to look very far for us - in fact, we will be looking for him.
"He can keep shooting his mouth off all he likes. After Scott makes his mandatory defence, Audley will be in our sights."