Barcelona were close to landing France World Cup star Antoine Griezmann but their failure to make an official move gave hope to United.
Griezmann himself has made a claim that his future may now be away from Spain.
Speaking after France's 4-0 Euro 2020 qualifying win in Andorra on Tuesday, he said: "I don't know if I will stay in La Liga.
"I know where I want to go. I am also keen to get this over with as quickly as possible.”
Now United are willing to pay his transfer fee and meet wage demands of around £450,000 per week something that is not easy for United with their current budget.
PSG are also interested in bringing the striker back home to France.