The midfielder had joined United two seasons ago in a then world record £89 million deal. But relations with manager Jose Mourinho hit a new low last term, with the player and the coach not sharing a comfortable rapport.
The French international, who won the World Cup with his nation this summer, is also believed to have sent a text message to Ed Woodward.
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Reports earlier stated that Barcelona made an offer worth £46 million for Pogba, which also included two players, viz. Yerry Mina and Andre Gomes. But United rejected the offer.
With the transfer window in England set to shut down on Thursday, Manchester United maintain that Pogba is not for sale.
The report also adds that a five-year deal has been agreed between the Reds and the player, with a basic salary of £18m equivalent to £346,000-a-week.
Pogba is said to have gotten frustrated with Mourinho, and wants to ply his trade in Spain. But it is unlikely that this move will prosper due to the very little time left.
The 25-year-old returned to training at Carrington on Monday, but it could still be too soon for the World Champions to star in United’s Premier League opener against Leicester City on Friday.