Just four years ago, Robertson was playing on a part-time basis for Queen's Park in the Scottish leagues and working in a supermarket.
"I know our environment will benefit him and help him push himself even more than he has already".
Speaking in the aftermath of the completion of the move, Robertson told Liverpoolfc.com: 'It feels a wee bit surreal just now.
In his first season as a professional he was named Scottish Young Player of the Year and also made his worldwide debut.
The move is good news for Dundee United too, as a sell-on clause was inserted into the deal that took Robertson south of the border.
The 23-year-old has revealed he is eager to prove he can play the top-level, having swapped the relegated Hull for Champions League participants Liverpool, and has hailed Jurgen Klopp's side as a "special club".
He has made 3 appearances for the senior Spanish side so far and if he wants to play for them at the World Cup next year, then regular club football in the upcoming season is a must.
Hull say on their official website that Stewart is available for selection in their friendly clash with Benfica on Saturday night, and the midfielder is understandably happy to seal the transfer.
"This signing strengthens us at full-back and I'm really pleased about this".
However, it seems privately they acknowledge every player has a price and it looks like Liverpool may have got their man as the Express are citing a report from Winner Sports that claims a £74.5m fee has now been agreed between the two clubs.
Said 23-year-old Stewart: "I'm delighted to sign for the club, I can't wait to get started and get my boots on".