A number of Premier League clubs are awaiting the outcome of the talks, with the striker set to be told by Louis van Gaal that he will be a rotation option this season.
Welbeck has already had meetings with Van Gaal this summer and a host of Premier League clubs - including Arsenal, Tottenham, Newcastle and Sunderland - are maintaining a watching brief should the England striker become available.
The 23-year-old will look to be reassured that he will receive regular football this coming season, but it is understood Van Gaal considers him a rotation option behind Wayne Rooney and Robin van Persie.
Welbeck has been at United since the age of 9 and would find it a wrench to move on, but believes he should be a starter.
He had previously expressed a desire to leave under former boss David Moyes after he was restricted to a role on the left-hand side, and although his urgency to leave was lessened by the Scot's departure he has kept an open brief over the summer as he weighs up his options.
United would likely ask for around 16 million pounds as Welbeck has two years remaining on his current deal, though Goal understands both Newcastle and Sunderland would only stretch as far as a loan.
And as well as north London rivals Arsenal and Tottenham, Hull City, Everton and West Ham are also keeping an eye on proceedings.
Welbeck already knows Sunderland well having spent the 2010-11 season on loan at the Stadium of Light.
The Black Cats have turned to Welbeck after they failed with their bids for Eduardo Vargas - who is signing for QPR - and Fabio Borini.
*Premier League 13-14 stats
Despite Sunderland agreeing to pay £14m for him in July, the Italian striker is not willing to make the move back to Wearside.
Even the imminent arrival of Mario Balotelli at Liverpool is not likely to convince Borini to make the move, especially as Goal understands Napoli could be ready to make their move in the final days of the transfer window.
Sunderland has therefore turned their attentions to Welbeck, but Newcastle is also monitoring the situation as it looks for another striker.
The Magpies had Lyon's Alexandre Lacazette and former loan striker Loic Remy at the top of their wanted list, but a move for Welbeck is now on their agenda.
Welbeck marked his Premier League debut with a 30-yard strike against Stoke City in 2008, and has scored a total of 26 league goals in 116 appearances.
He struck nine times in the top division last season, his best to date, after hitting the net just once in 2012-13 in Sir Alex Ferguson's final season.