"I think that he's fantastic," Schwarzenegger said in an interview with CinemaBlend. "He was, always for years and years, is a huge, huge star. And I think that he will always be remembered as a great, great star. And a kind man. I understand that under his circumstances, health-wise, that he had to retire. But in general, you know, we never really retire. Action heroes, they reload."

Last year, Willis' daughter Rumer announced via Instagram that her father had been diagnosed with aphasia, which affects language abilities, and was "stepping away" from his career.

"We wanted to share that our beloved Bruce has been experiencing some health issues and has recently been diagnosed with aphasia, which is impacting his cognitive abilities," she wrote. "As a result of this and with much consideration Bruce is stepping away from the career that has meant so much to him."

Schwarzenegger has long been an admirer of Willis. In the new book The Last Action Heroes: The Triumphs, Flops, and Feuds of Hollywood's Kings of Carnage, author Nick de Semlyen recounts how the Austrian actor "guffawed through a screening of the movie at Fox, not least at the moment when McClane exclaims, 'They have missiles, automatic weapons, and enough plastic explosives to orbit Arnold Schwarzenegger!'"