The French centre-back missed Liverpool???s 2-0 victory at Southampton last weekend and did not travel with his team-mates to Istanbul for their Europa League game against Besiktas.
And tweets from the 25-year-old on Thursday appear to cast doubt on his availability for Sunday???s match against City, live on Sky Sports 1 HD.
He wrote: ???Good news as following the tests I had at the beginning of the week and after the medical staff ‘s opinion…
???… i can go back to training with the group on Saturday! Minewhile (sic), I wish good luck to the whole team for tonight !???
Sakho had featured in nine straight Premier League games for Liverpool before picking up a hip injury which forced him to miss Sunday???s visit to St Mary???s.
He joined for Liverpool for a fee of ??17m from Paris Saint Germain at the end of the 2013 summer transfer window.