The defender is expected to leave Liverpool this month, with the club's hierarchy seeking a fee in the region of £20m for the 26-year-old.
Sky Sports News HQ reporter Vinny O'Connor said: "Sakho was left out of Liverpool's U23 squad yesterday. It's not the first time this month he's been left out.
"The reason behind it is simple. It's Liverpool's intention to move him on this month. Indeed, the likelihood is that he will leave in this transfer window.
"Liverpool are looking to sell for £20m and are not entertaining loan deals at the present moment in time either.
"As it stands, nothing is imminent and his withdrawal from the U23 squad isn't a signal that a deal is imminent."