The Reds have been linked with the defender for a number of weeks while Pompey executive chairman Peter Storrie claimed last week Johnson’s former club Chelsea were willing to pay £18m for the 24-year-old.

A Liverpool statement read: “Liverpool confirm they had reached an agreement with Portsmouth and with Glen Johnson for the transfer of the player to Anfield.”

Johnson enjoyed arguably his best season in the Premier League last term as he established himself as England’s first-choice right-back and attracted the interest of bigger clubs.

Storrie admitted last week that there was every chance Johnson could leave Fratton Park this summer, especially with the size of the fee being talked about.

Rafael Benitez has not spoken of his interest in Johnson – many Reds fans would prefer him to reinforce his squad in other areas – but Johnson’s impending arrival would seem to suggest Alvaro Arbeloa will be sold to Real Madrid sooner rather than later.

Johnson’s first crack at the big time fizzled out when, after joining Chelsea from West Ham in 2003, he struggled to secure a regular first-team place and was loaned to Portsmouth before making the move permanent in 2007.

Storrie said last week: “Glen has obviously had a fantastic season season for us and has established himself as one of the best right-backs in the league if not the country at the moment.

“I’ve known Glen for a long time since his West Ham days so when I re-signed him we talked it over and he asked if one of the big four clubs, who were in the Champions League, came in for him would we stand in his way of a move.

“I said that I couldn’t do that provided the deal is good for Portsmouth and for Glen.”