The Merseyside club are currently in Melbourne for the second game of their pre-season tour in Australia where they will take on new A-League outfit Melbourne Heart tomorrow night at Etihad Stadium and Moyes was full ok kind words for the Australia international.
"He's a big player for Australia, he's a key player for them and he has been over the years and hopefully he will continue to be for many more to come," Moyes told reporters today.
"He'll play some of the game (against the Heart). You've got to remember he's just back from a World Cup, I wanted him to be on holiday, but we happen to be in his country. He's really keen to be here and show off his country to the team and everybody else and also we would like him here because I know it's important for the Australian public to see him. They don't see him play live that often so I'm aware of that but I've obviously got to make sure I get the best out of Tim for the start of next season and that he does get some holiday time."
Moyes signed Cahill to Goodison Park in 2004 when he was with Millwall and says since then he has only improved his game and has now become a premier player.
"I rate him very highly. He was one of my early signings when I bought him from Millwall," he added. "I remember going with the chairman to the game and we sat there and watched and I'd been managing Preston at the time, we were in the same division as Millwall and I always quite liked him and I always thought maybe so I took the gamble on Tim.
"He's very good in both boxes, he can score, he can defend, so I thought from that point of view he would always offer us something and he has certainly not disappointed as a player and as a person to have around the club - he has been excellent."