Ole Gunnar Solskjaer is desperate to bolster his squad ahead of the October 5 transfer deadline, having suffered a shock 3-1 defeat at home to Crystal Palace in their opening Premier League fixture last weekend.
Sancho, 20, has long been on their radar, yet Borussia Dortmund’s £108million asking price has so far proved stumbling block in negotiations.
Daily Star Sport understands United are set to launch a first and final £90million offer for the England star, nonetheless, which would see them pay £75million upfront and £15million in add-ons.
As for Telles, the Red Devils are keen to prise him away from Porto this summer.
The Brazilian left-back is valued at around £18million, which they feel is too much for a 27-year-old in the final year of his contract.
According to The Sun, United are looking to sign both players within the coming weeks.
Executive vice-chairman Ed Woodward and transfer guru Matt Judge are said to be in constant discussions to get the deals over the line, with just nine days to go until the window closes.
Sancho is ready to join United before the deadline, although he will not try and force a move to Old Trafford.
The same can be said for Telles, who is relaxed about his own transfer situation.
Sky Sports reporter Kaveh Solhekol claims United are ‘quietly confident’ about signing Sancho, despite Dortmund’s insistence on a £108million transfer fee.
“As far as I understand it, Manchester United are quietly confident that there is a good chance they will get their No.1 target Jadon Sancho,” Solhekol said on The Transfer Show.
“If you look at it, this has been going on for eight weeks now and United haven’t made a bid.
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“But the reason you could say that has happened is because Borussia Dortmund are asking for too much money.
“So what do Manchester United do? In this kind of situation, the logical thing to do is wait until the end of the window before you make your move. Just wait, bide your time, and then in the last week or the last few days make that offer.”