Ole Gunnar Solskjaer’s side are edging ever-closer to sealing a £110million ($A200m) deal for the England international.
German runners-up Dortmund insist United must seal the deal by August 10, when their players is expected back for pre-season training.
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Sancho, 20, sparked rumours a deal is imminent as he returned to his homeland, and was spotted at a party hosted by rap stars Krept and Konan on Saturday.
However, it is understood no agreement has yet been reached.
And Dortmund’s communications chief Sascha Fligge said there is no problem with Sancho returning to England as long as he reports back for training as normal.
Fligge said: “It’s common and fine for players to go home before a training camp if they’re not risky.
“The same goes for Jadon [Sancho].
“From our point of view, the pictures that have been shown to us so far do not violate.”
United are understood to see the German side’s deadline as meaningless with the transfer window open until October 5.
On Saturday SunSport reported meeting the eye-watering price tag for Sancho, 20, might lead to United potentially blowing their entire transfer kitty on one player.
It could mean that moves for other targets, including Aston Villa captain Jack Grealish, are likely to be off the table.
This article was first published on The Sun and was reproduced with permission.
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