The Red Devils saw a third bid of £50million, plus £5m in add-ons, rejected last week.
talkSPORT understands talks have never stopped and Mount remains United's key midfield target of the summer.
United have been unwilling to meet Chelsea's valuation of the 24-year-old, who has just one year left on his contract.
Chelsea are believed to want £57m, plus £8m in add-ons, with negotiations reaching an impasse.
Man United believe their valuation is fair, especially given the player is keen on a move to Old Trafford.
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Their offer of £55m remains on the table, but there could be further developments this week should more positive talks take place.
Brighton's Moises Caicedo is another option, should the Red Devils fail in their attempts to lure Mount to the club.
talkSPORT understands United have spoken to the Seagulls about Caicedo.
The 21-year-old Ecuador international has an £80m price tag slapped on him.
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As well as a midfielder, Ten Hag is keen to sign an attacker with Atalanta's Rasmus Hojlund a top target.