Virgil van Dijk, Mohamed Salah and Trent Alexander-Arnold are all due to come off contract in June.
On Salah's goalscoring performance in Sunday's win against Manchester City, Mac Allister told ESPN: "I think it shows a little about who Mo is, his mentality. When you see him every day, he is a person who works very hard, who is tireless. He is the first to come and the last to go.
"Always prepared for whatever may happen. He brings it to the pitch and he always helps us in crucial moments. When big players get tougher, he's there. It makes us all happy.
"Of course we want to share many years with him, but it is a personal decision. The club has to make a decision and we cannot get involved.
"Hopefully they can come to an agreement because we want him, Virgil and Trent to continue with us. Hopefully it will be like that."
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