Manchester United have made a 28.6 million pound ($45 million) bid for Real Madrid defender Sergio Ramos, British media reported on Monday.
Media reports said the 29-year-old Spain international was keen to move to Old Trafford, despite having two years left on his Real contract.
United manager Louis van Gaal is seeking to shore up the Premier League club's defence to help improve on last season's fourth-place finish.
United confirmed earlier on Monday that defender Phil Jones had signed a contract extension until at least 2019.
READ MORE
Fernandes equals assist record as Man Utd edge Forest thriller
Real Madrid start presidential election process
Barcelona need a point against Real Madrid to win La Liga
Carrick says strong finish matters more than his Man United future