MANCHESTER, England -- Manchester United are determined to resist attempts by Tottenham to include Anthony Martial in any deal for Toby Alderweireld, sources have told ESPN FC.

United are keen to take advantage of Alderweireld's contract standoff with Tottenham to bring the defender to Old Trafford this summer.

Spurs, meanwhile, hold an interest in 22-year-old Martial, who has become frustrated at a lack of opportunities following Alexis Sanchez's arrival in January.

But while sources have confirmed Tottenham are resigned to losing Alderweireld, United are hopeful of keeping hold of Martial and will only listen to offers if he pushes for a move.

Alderweireld, 29, has two years left on his contract but with little prospect of an extension being agreed, Spurs are willing to cash in if they receive a fee in the region of £50 million.

Anthony Martial has cut a frustrated figure at times this season for Manchester United. Simon Stacpoole/Offside/Getty Images

Martial, who started just four Premier League games between February and May, was only named among the substitutes for the FA Cup final defeat to Chelsea and missed out on a place in France's World Cup squad.

Jose Mourinho has made it clear that any player wanting to leave this summer can go for the right price but sources have said that if Martial -- who is also on Juventus' radar -- makes it clear he is determined to move, United would prefer to sell to a club outside the Premier League.

Sources have also said that Mourinho, who is closing in on a deal for Shakhtar Donetsk's Brazilian midfielder Fred, will step up his interest in Chelsea winger Willian if Martial departs.

Meanwhile, ESPN FC has been told that Matteo Darmian is moving closer to a return to Italy with Juventus.

The 28-year-old, who arrived from Torino for £12.7m in 2015, made just five Premier League starts last season and is likely to cost the Serie A champions around £10m.