Manchester United have finally been given the go-ahead to close in on Mats Hummels and install him as their new defensive lynchpin at the end of the season.

Sportsmail understands that, after years of staying loyal to Borussia Dortmund and resisting overtures from United, the Germany centre-back has decided he's ready to cut his ties with the fallen Bundesliga giants and move on.

He is fully aware of continuing interest from Old Trafford and is believed to have set his sights on becoming the latest big-name addition to an expensive United refit under Louis Van Gaal.

Manchester United target Mats Hummels is prepared to leave Borussia Dortmund for a new challenge

The Dortmund defender clears a ball off the line during Saturday's 3-2 Bundesliga win over Hannover

Hummels looks on dejectedly as Juventus knock Dortmund out of the Champions League last 16

HUMMELS' SILVERWARE With Borussia Dortmund Bundesliga: 2010–11, 2011–12 DFB-Pokal: 2011–12 DFL-Supercup: 2013, 2014 Champions League: Runners-up: 2012–13 With Germany FIFA World Cup: 2014 Advertisement

The one stumbling block could be the asking price, with Dortmund willing to grant Hummels' wish, but only on their terms. They want £36million for the 26-year old and are reluctant to accept less.

Van Gaal is unlikely to be deterred, though, and will urge club bosses to open talks in an attempt to agree a valuation for a defender who has the experience and know-how United need at the back.

The pursuit of Dortmund skipped Hummels dates back to the 2011-12 season, when Sir Alex Ferguson attended the German Cup final to watch Jurgen Klopp's side crush Bayern Munich 5-2.

It completed an historic league and cup double for Dortmund and led to Ferguson launching a bold bid to lure Hummels, Robert Lewandowski and Shinji Kagawa away from the Westfalenstadion.

Louis van Gaal needs defensive reinforcements at Old Trafford but may be forced to stump up £36m

Jurgen Klopp's side have struggled this season, spending part of the campaign in the relegation spots

Repeated approaches for Hummels always met with stubborn resistance from Dortmund, but they have been forced to back down after their cultured defender indicated he was unhappy with their fall from grace this season.

A sharp decline in fortunes briefly left them embroiled in a relegation battle, and though an overdue revival steadied the ship, there still seems little prospect of Champions' League football next season..

Hummels feels he has remained loyal long enough and is hoping United's negotiators can come up with a package that will smooth the way for his long-awaited arrival at Old Trafford.