Jacobs, speaking to The United Stand, confirmed United's interest while making clear the obstacle.
"Chelsea have always said he is just not for sale. And I am led to believe that's a genuine stance. But Acheampong, who is also on the radar of Manchester City, is going to have to understand heading into the new season under a new manager how often he is going to play — because Chelsea are looking to sign another new starting centre-back."
He added that despite Chelsea's public position, the player himself would be open to exploring alternatives if he concludes regular first-team football will not be guaranteed under incoming head coach Xabi Alonso.
"My information is that the player would be interested in exploring options if he feels he's not going to be getting regular game time next season."
Acheampong, who turned 20 in March, made 16 Premier League appearances this season, starting eight. He is a versatile defender capable of operating at right-back and centre-back, and stands 6ft 3in — a profile that suits Michael Carrick's requirement for a long-term successor to Harry Maguire at Old Trafford.
Chelsea signed Acheampong at Under-9 level and he has progressed through every age group at Cobham. His contract runs until 2029, giving the west London club full negotiating leverage. There is no indication the club will soften their stance regardless of United's interest.
Bayern Munich, Real Madrid and Liverpool have all been linked with Acheampong in recent months. The breadth of interest reflects both the quality of the player and the frustration around his lack of consistent minutes at Stamford Bridge.
Carrick has prioritised midfield reinforcements this summer. The Acheampong link suggests defensive options are also being explored further down the list.