"I've never asked to leave but I was very disappointed with the offer they made me," Melville told the London Evening Standard.
"I've turned it down and as things stand I will be available on a free transfer in the summer.
"I've got no problem with just a year extension because, at 34, I'm realistic about how long I've got left at the top level but their offer meant taking a significant cut in my basic wage, which I wasn't happy about."