West Ham are interested in signing Sporting Lisbon midfielder William Carvalho, according to Sky sources.
The Portugal international, who joined Sporting Lisbon in 2012, is understood to want a move to the Premier League.
The 25-year-old midfielder, who has scored nine goals in 137 appearances for the club in four seasons, has a £40m release clause in his contract which still has three years remaining.
Angola-born Carvalho was an integral part of the Portugal team which won the European Championships in France last summer and has previously been linked with moves to Arsenal and Manchester United.
West Ham have already signed strikers Javier Hernandez and Marko Arnautovic this summer, but manager Slaven Bilic is keen to add further options to his squad.
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