They are aiming to take Tom Adeyemi on a season-long loan from Cardiff City.
The 23-year-old midfielder is set to join Leeds in a deal which will give the Elland Road club an option to sign him permanently next summer.
Adeyemi is out of favour at Cardiff but United head coach Uwe Rosler plans to take him for the 2015-16 term with a view to securing Adeyemi on a three-year deal in 12 months’ time.
The 6’1” youngster played under Rosler while the German was manager of Brentford, one of three loans Adeyemi completed during his time with Norwich City.
He left Carrow Road to join Birmingham City in 2013 and was signed by Cardiff a year ago. His chances at City were limited, however, following the sacking of former boss Ole Gunnar Solskjaer last September.
Rosler has been targeting a holding midfielder throughout the summer and his search intensified after midfielder Luke Murphy was lost to a minor knee injury a fortnight ago.
Murphy has undergone surgery and will miss the start of the new Championship season. The 25-year-old could be out for up to seven weeks.
Despite that setback, it is understood that Murphy is on the verge of agreeing a new contract at Elland Road. Murphy, who cost £1m from Crewe Alexandra in 2013, is currently tied to United until the end of this season but is expected to extent that deal by a further two years.
Adeyemi, meanwhile, looks set to become Leeds’ fifth summer signing following the arrival of goalkeeper Charlie Horton, defender Sol Bamba and strikers Chris Wood and Lee Erwin.
Adeyemi has amassed more than 120 league appearances during his career.