St John made 425 appearances for the Reds and scored 118 goals as a key member of Bill Shankly's famous side of the 1960s.

The Premier League club confirmed St John died on Monday evening following a long illness.

"We are deeply saddened by the passing of a true Anfield legend, Ian St John," the Merseyside outfit said.

"The thoughts of everyone at Liverpool Football Club are with Ian's family and friends at this sad and difficult time. Rest in peace, Ian St John 1938-2021."

The St John family said he passed away peacefully with his family at his bedside.

"It is with a heavy heart that we have to inform you that after a long illness we have lost a husband, father and grandfather," the family said in a statement on Liverpool's website.

St John won two first division titles under Shankly and scored the winning goal in Liverpool's FA Cup final in 1965.

The forward also represented Scotland 21 times, scoring nine goals.

After retiring in 1973, St John went on to manage his hometown club Motherwell and also Portsmouth.

But he won a new generation of fans in the 1980s presenting the popular UK soccer show Saint and Greavsie alongside former Tottenham and England forward Jimmy Greaves.

"We are very sad to hear the Saint has passed away," Greaves posted on Twitter.

"He was a lovely man and will be sadly missed by many, many people."

Former Liverpool forward and manager Sir Kenny Dalglish said it was right to use the word "icon" for St John.

"It's because of what he did in those early days, Shanks especially, the Saint and Big Yatesey (Ron Yeats) ... it's because of them where this football club is at this particular moment in time.

"We should be eternally grateful for what he did for the football club."

Ex-Reds captain Steven Gerrard, who manages Scottish club Rangers, heard the news during a Rangers press conference.

"I'm really disappointed to hear that. He's an iconic figure at Liverpool Football Club," he said.

"A fantastic guy. Really insightful in terms of his career and experience at Liverpool and trying to pass on a lot of knowledge and expertise.

"So I'm really devastated to hear that news."

St John began his career with Scottish club Motherwell in 1957 and scored 80 goals in 113 league games.

Australian Associated Press