Stallone publicly slammed Willis for being "greedy" while announcing that Harrison Ford was replacing him. He took to Twitter to express his anger, tweeting "GREEDY AND LAZY... A SURE FORMULA FOR CAREER FAILURE."
Willis, 58, was reportedly offered USD 3 million for four days of work shooting in Bulgaria but said he would drop out if he didn't get USD 4 million, according to the Hollywood Reporter.
"He said he'd drop out unless he got USD 4 million. A illion dollars a day. Stallone and everybody else involved said no," a source close to the production said.
The next installment of "The Expendables" is set for release next August by Millenium Films.
The action movie has a star-studded cast of Arnold Schwarzenegger, Jason Statham, Mickey Rourke, Wesley Snipes and Jackie Chan.