The 18-year-old French midfielder is out-of-contract this summer, and United - who lured him from Le Havre in 2009 - are desperate to tie him down to a new deal.
Talks are on-going but sources in England and Italy both claim that Juventus and AC Milan are offering him bigger money than United.
"It is a precarious situation," his agent Mino Raiola is quoted as saying by The Independent.
"It is difficult at the moment. Manchester United want him. It is up to the boy to make some decisions.
"We know there are some clubs interested in him.
"We must finish first with Manchester and after that we will see other options, if they are there.
"The club give the indication that they want to keep him and we are talking contract terms. There is willingness from both parties at the moment."
Raiola confirmed that Pogba was not happy to be left out of the United squad to face Ajax in the Europa League last week.
"It is never nice for the player not to be in the squad. It is the same for [Mario] Balotelli [whom Raiola also represents.]
"We must keep our minds cool and heads cool. Some things are good. Some things are not good [in this situation]."