In a sign the talks between the two clubs are on track, with claims a £10m fee has been agreed, Robertson has now jetted back from Hull's tour of Portugal.
Earlier on Wednesday, the East Yorkshire side announced the sale of goalkeeper Eldin Jakupovic to Leicester City for an undisclosed fee.
Meanwhile, RB Leipzig's owner says the German club have rejected a 75m euro (£66m) bid for midfielder Naby Keita.
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Effectively, we're offloading an unwanted, unneeded midfielder and securing a talented young left-back - at no extra cost.
Former Liverpool striker Stan Collymore has commented on Andrew Robertson's seemingly imminent move to Anfield, and he is clearly impressed by the 23-year-old.
He signed a five-year contract with Liverpool last November, but has found himself down the pecking order, and has seen interest from Premier League sides Stoke City, Brighton & Hove Albion and Burnley before opting for Hull.
According to BBC Radio Humberside's Mike White, Liverpool have accepted season-long loan offers from Hull, Leeds United and another, as yet unknown, club.