Jose Mourinho is determined to strengthen his defence with a new centre-back and will offer Roma £47.6million for Kostas Manolas.
The Manchester United manager has said he does not intend to buy another defender but behind the scenes is still working on a deal for the Greek international.
Mourinho had initially coughed up £32.5m for Manolas.
That came after talks with Victor Lindelof hit a wall – despite Benfica and Vasteras recently agreeing a sell-on fee.
And last May, when Mourinho started looking at which players he would like to sign, he paid special attention to Manolas and team-mate Alessandro Florenzi.
But Roma, who currently sit just four points behind Serie A leaders Juventus, are reluctant to lose one of their most sought-after assets.