Longstaff was previously linked with a move to Old Trafford only for the trail to have gone cold recently.
Despite making only eight Premier League appearances for Newcastle, the 21-year-old is already being talked about as the ‘new Michael Carrick’, after some impressive performances.
He was ruled out for the season in March after suffering a knee ligament injury, but this has not hindered United’s interest with a £40m bid being touted.
And according to the London Evening Standard, United have prepared an offer for the midfielder but they will not pursue a deal until they have dealt with the problems at right-back and centre-half.
Solskjaer is in desperate need of defensive reinforcements and despite several names being linked, they are yet to get anyone over the line.
The Red Devils have had an opening £40m bid for Crystal Palace full-back Aaron Wan-Bissaka rejected but are expected to return with an improved offer.
In central defence, Manchester United have been heavily linked with Matthijs de Ligt, Kalidou Koulibaly and Harry Maguire, but, again there has been nothing concrete confirmed as yet.
Once they have sorted out these problem positions however, a return for Longstaff could be on the cards.
“I’m 100 per-cent focused on Newcastle”
United have already secured the signing of 21-year-old Daniel James from Swansea and are thought to be keen on bringing in young, British talent moving forward.
Longstaff then would fit the bill, but a deal may not be that clean cut.
The Geordie youngster insists he wants to remain on Tyneside and United could face an Alan Shearer situation where refuses to move elsewhere.
Speaking recently to NUFC TV about the links with United, Longstaff said: “It just shows how far I’ve come.
“If someone told us at the start of the season that by the end of it you’d be linked with these teams I’d have laughed at them but it’s nice, it’s flattering.
“I’m massively flattered to have my name even mentioned in those conversations but like I said, I’m 100 per-cent focused on Newcastle and trying to get fit and get back in the team here.
“For me it’s nice to be have said about you and be linked with top clubs but for me, this is what I’ve always wanted to do.
“I’ve always wanted to play for Newcastle and I’ve only had a little taste of that so for me, it’s about getting fit as soon as I can and getting back on the pitch for Newcastle and making more memories of the future.”