Manchester United are about to make a formal offer for striker
Benjamin Sesko after Newcastle bid £69.8m over the weekend.
United have been in talks with Leipzig over what they would be prepared to pay.
Newcastle are also in ongoing talks over the structure of a deal after making their official bid.
Sesko is open to both projects but a source told
Sky Sports News he is leaning towards United if they can agree a deal.
United's pursuit of Sesko throws into question
Rasmus Hojlund's future at Old Trafford with the club understood to be listening to suitable offers for the striker.
It was thought United would have to make sales in order to bring in a striker. However, while the priority is to offload players, it is understood Ruben Amorim's side can buy before selling, provided there are sales before the window closes.
It is understood RB Leipzig are interested in Hojlund and have explored the conditions of a loan. Leipzig had proposed taking the striker on loan as part of any possible deal for Sesko.
Hojlund started the first two games of the club's pre-season tour of the United States, coming on as a substitute in a 2-2 draw against West Ham, and has publicly said he wants to stay and fight for his place, but the possible arrival of a new striker could limit his game time.
A scenario where Sesko joins and Hojlund stays cannot be ruled out.
Sesko was absent from RB Leipzig's pre-season friendly loss to Atalanta on Saturday due to his expected departure from the club. The striker has reportedly told his team-mates that he will be leaving, according to Sky in Germany.
Marcel Schafer, RB Leipzig's managing director for sport, confirmed clubs have made approaches for Sesko.
"We won't go into detail on that but when I say that several clubs have shown strong interest and have made approaches, it's obvious what has happened," he said.
Newcastle are also interested in Yoane Wissa, who was not part of Brentford's squad for their friendly against QPR on Saturday as he pushes for a move.