The development comes following reports that the unsettled England international requested not to participate in the club’s pre-season tour of the Far East and Australia.
Liverpool began pre-season training this week but it is believed Sterling telephoned yesterday morning to say that he was unwell.
The club have not commented on the situation.
Sterling, 20, has been the subject of two failed bids from Manchester City this summer.
The player, who has two years remaining on his contract at Anfield, rejected an offer of a new £100,000-per-week deal earlier this year.
It is understood that Sterling spoke to manager Brendan Rodgers this week and informed him that he did not want to travel on the pre-season tour. Rodgers and his squad are due to fly out on Sunday ahead of their first friendly against a Thai All Stars side in Bangkok next Tuesday.
Since reports of Sterling’s tour request emerged, a mobile phone number purportedly of the player’s has been posted online with disgruntled fans encouraged to use it to send abusive messages.
The club have not commented on whether the number is genuine.
The Sterling saga is becoming increasingly acrimonious with the player seemingly intent on forcing through a move.
City have maintained a silence on the issue but it is claimed they could be preparing another bid of around £50 million.
Former Liverpool defender Jamie Carragher believes the way the whole affair is playing out could be causing long-lasting damage to Sterling’s standing.
“He’s starting to get a reputation that could be hard to rid himself of in the future,” Carragher said.
“Are Man City fans looking at the situation and thinking this could be us in a few years?
“I think this situation will only make Liverpool more determined to get the fee they feel Raheem is worth rather than caving in to Raheem’s and Man City’s wishes.”
Meanwhile, Toby Alderweireld may have completed a dream move to Tottenham — but the Belgium defender could still be involved in a legal wrangle between Southampton and Atletico Madrid.
The 26-year-old moves to White Hart Lane having spent last season on loan with Ronald Koeman’s Southampton, who had a deal in place to sign the former Ajax man.
Under the terms of the loan, Atletico could pay £1.5m to Saints to cancel that agreement but the south coast club claim that the La Liga outfit did not do so in time and therefore believe they should have been the front-runners to sign Alderweireld.
Despite the uncertainty over any outstanding fee or potential legal proceedings, the player completed a move to White Hart Lane.
“I’m very proud to become a Spurs player,” he said.
“I’m very happy to be here and I hope to have a wonderful time with this team.
“I know the players from the national team and I played with Jan at Ajax, we had a central defensive partnership. It’s nice when you join another club that you know a couple of players. I hope to get to know them a little better now.
“It’s a big club and it’s always been a dream to play at a club like Spurs. Now that dream is coming true so I’m very happy, very proud and I will give my best.”